API marketplace

Validate the bank and provider identifiers that move money and records — all checked locally, with no lookups. The bic endpoint validates and parses a SWIFT/BIC code (ISO 9362): it confirms the 8- or 11-character format, splits out the bank, country, location and branch codes, checks the country against ISO 3166, and flags test and passive-participant codes. The aba endpoint validates a US ABA routing number by its checksum (the 3-7-1 weighting) and names the Federal Reserve district from the prefix. The npi endpoint validates a US National Provider Identifier by its Luhn check digit over the 80840 prefix and reports whether it is an individual or organization NPI. Everything is computed locally and deterministically, so it is instant and private — it checks the structure and check digits, not whether the institution actually exists. Ideal for payments and banking, fintech onboarding and KYC forms, healthcare billing and clearinghouses, and form and data validation. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. This validates BIC, ABA and NPI; for IBAN use an IBAN API and for payment-card numbers use a credit-card API.

Uptime

100.0%

Latency

80ms

Subs

3,913

Acoustics and decibel maths as an API. The decibel endpoint converts between a linear ratio and decibels, in either the power convention (10·log₁₀) or the amplitude/pressure convention (20·log₁₀), in both directions. The combine endpoint adds sound levels the way real (incoherent) sources combine — by energy summation, so two equal 80 dB sources give 83 dB, not 160 — and can also subtract a known source from a measured total. The distance endpoint applies the inverse-square law to a point source in a free field (−6 dB per doubling of distance) to find the level at a new distance. The wavelength endpoint converts between frequency and wavelength for sound, deriving the speed of sound from the air temperature (or a value you provide). Everything is computed locally and deterministically, so it is instant and private. Ideal for audio engineering and live sound, room and architectural acoustics, noise assessment and environmental monitoring, and physics teaching. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 5 endpoints. This is acoustics maths; for electrical circuits use an Ohm's-law API and for general unit conversion use a unit API.

Uptime

100.0%

Latency

72ms

Subs

3,860

Bit-level integer maths as an API, at 8-, 16-, 32- or 64-bit width with exact big-integer arithmetic. The inspect endpoint takes a number (decimal, 0x hex, 0b binary or 0o octal) and returns its decimal, signed (two's-complement), hexadecimal, binary and octal forms, plus the population count (Hamming weight), parity, leading and trailing zero counts, whether it is a power of two, its bit-reversed value and its byte-swapped (endianness) value. The ops endpoint performs a bitwise operation — AND, OR, XOR, NAND, NOR, XNOR, NOT, logical and arithmetic shifts (shl, shr, sar) and rotations (rol, ror) — masked to the chosen width. The bit endpoint sets, clears, toggles or tests an individual bit by index. Everything is computed locally and deterministically, so it is instant and private. Ideal for embedded and systems programming, network-protocol and flag handling, graphics and hashing, emulators and reverse engineering, and teaching binary. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. This is bit manipulation; for base 2-36 conversion use a base-convert API and for IEEE-754 floating-point bits use a floating-point API.

Uptime

100.0%

Latency

87ms

Subs

3,665

Pregnancy and due-date maths as an API, using the standard Naegele's rule (40 weeks / 280 days from the last menstrual period). The due-date endpoint takes the last menstrual period, the conception date, or a known due date — whichever you have — and returns the due date, the estimated conception date and the fertile window. The gestational-age endpoint reports how far along a pregnancy is as of any reference date: gestational age in weeks and days, the trimester, days remaining, progress percent, and whether it is overdue. The milestones endpoint lists the key dates of a pregnancy — the trimester boundaries, the anatomy-scan window, viability at 24 weeks, full term at 37–40 weeks, the due date and post-term at 42 weeks. All dates are handled in UTC and computed locally and deterministically. Ideal for pregnancy and fertility apps, midwifery and clinical tools, and parenting and family-planning products. Informational only — not medical advice. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. This is pregnancy date maths; for general date arithmetic use a datetime API.

Uptime

100.0%

Latency

73ms

Subs

3,484

CIE colour science as an API: convert colours through the device-independent spaces and measure how different two colours really look. The convert endpoint takes a colour as hex, RGB or CIELAB and returns it in sRGB hex, RGB, CIE XYZ and CIELAB (D65 white point). The distance endpoint computes the perceptual difference between two colours with all three standard Delta-E formulas — CIE76 (plain Lab distance), CIE94, and CIEDE2000, the modern and most accurate metric — and tells you whether the difference is perceptible. The nearest endpoint finds the closest named colour to any colour by CIEDE2000. This is the maths behind colour matching, print and brand-colour QC, and tolerancing — distinct from simple hex/RGB/HSL conversion. Everything is computed locally and deterministically, so it is instant and private. Ideal for print and prepress, brand-colour compliance, textile and paint matching, image processing and computer vision, and design tooling. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. This is CIE colour difference; for hex/RGB/HSL/CMYK conversion, palettes and WCAG contrast use a colour API.

Uptime

100.0%

Latency

79ms

Subs

3,499

Meteorological formulas as an API — the derived weather figures, computed from your own readings, with no data feed or key needed. The wind-chill endpoint gives the "feels like" cold using the Environment Canada formula in metric (°C, km/h) or the US NWS formula in imperial (°F, mph), and flags when the reading is outside the valid range. The heat-index endpoint gives the apparent temperature from heat and humidity using the NWS Rothfusz regression with the standard low- and high-humidity adjustments. The dew-point endpoint uses the Magnus formula to turn temperature and relative humidity into the dew point, and also returns the vapour pressure and the absolute humidity. The beaufort endpoint maps a wind speed (m/s, km/h, mph or knots) to its Beaufort force and description, or a force back to its speed range. Everything is computed locally and deterministically, so it is instant and private. Ideal for weather apps and dashboards, agriculture and HVAC, marine and aviation, and outdoor and safety tools. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 5 endpoints. This computes weather formulas from your own readings; for live forecasts and observations use a weather data API.

Uptime

100.0%

Latency

73ms

Subs

4,194

Music-theory maths as an API, in equal temperament with A4 = 440 Hz and scientific pitch notation (C4 = middle C = MIDI 60). The note endpoint converts freely between a note name (A4, C#5, Eb3), a MIDI note number and a frequency — and when you pass a frequency it returns the nearest note and how many cents sharp or flat it is. The interval endpoint gives the distance between two notes in semitones and cents, its name (perfect fifth, major third, …) and the exact frequency ratio. The chord endpoint returns the notes, MIDI numbers and frequencies of a chord from a root and a quality (major, minor, dim, aug, sus, 6, 7, maj7, m7, dim7, m7b5, 9 and more). The scale endpoint returns the notes of a scale or mode from a root — major, the three minor scales, the seven church modes, the major and minor pentatonics, blues, whole-tone and chromatic. Sharp or flat spelling is selectable. Everything is computed locally and deterministically, so it is instant and private. Ideal for music apps and games, synthesizers and DAWs, ear-training and theory teaching, tuners and MIDI tools. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 5 endpoints. This is music theory; for searching tracks and artists use a music API and for the classical repertoire use a classical-music API.

Uptime

100.0%

Latency

72ms

Subs

3,938

Electronics circuit maths as an API. The ohms-law endpoint takes any two of voltage, current, resistance and power and returns all four (V = IR, P = VI = I²R = V²/R). The combine endpoint computes the total of resistors, capacitors or inductors wired in series or parallel — resistors and inductors add in series and combine reciprocally in parallel, while capacitors do the opposite. The voltage-divider endpoint computes the output voltage of a two-resistor divider and the current through it. The reactance endpoint computes capacitive reactance (Xc = 1/2πfC), inductive reactance (XL = 2πfL), the LC resonant frequency, and the RC or RL time constant. Everything is computed locally with exact formulas in SI units, so it is instant and private. Ideal for electronics design and education, embedded and hardware engineering, hobby and bench projects, and physics teaching. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 5 endpoints. This is circuit maths; for resistor colour codes use a resistor API and for general unit conversion use a unit API.

Uptime

100.0%

Latency

76ms

Subs

4,043

Resolution, print-size and pixel-density maths for print, design, photography and screens. The resolve endpoint takes any two of pixels, DPI and physical length and computes the third, returning the size in inches, centimetres, millimetres and points — so you can answer "how big will a 3000-pixel image print at 300 DPI" or "what DPI do I get printing 3000 px at 10 inches". The ppi endpoint computes a screen's pixel density from its resolution and diagonal size, plus the dot pitch in millimetres, the total megapixels and the aspect ratio. The convert endpoint converts a length between pixels, inches, centimetres, millimetres and points (PostScript points, 1/72 inch), using a DPI when pixels are involved. Everything is computed locally and deterministically, so it is instant and private. Ideal for print and prepress, graphic and web design, photography, and screen and display specs. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. This is DPI and print-size maths; for aspect ratios and resizing use an aspect-ratio API and for general unit conversion use a unit API.

Uptime

100.0%

Latency

76ms

Subs

3,639

Re-map text between keyboard layouts — the fix for text typed with the keyboard set to the wrong layout. The remap endpoint takes text, a source layout and a target layout, and rewrites each character to the one produced by the same physical key on the other layout. So text accidentally typed on a Dvorak-configured keyboard while you meant QWERTY (or the reverse) is recovered exactly, and because the mapping is position-preserving it round-trips perfectly. It supports QWERTY (US), Dvorak and Colemak, including the shifted symbols, and leaves characters that are not on a remappable key (spaces and accents) untouched. The layouts endpoint returns the full key map for each layout. Everything is computed locally and deterministically, so it is instant and private. Ideal for fixing wrong-layout typing, building text editors and IME tools, layout-learning aids, and cross-layout search. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This remaps between keyboard layouts; for classical ciphers (Caesar, ROT13, Morse) use a cipher API.

Uptime

100.0%

Latency

81ms

Subs

4,338

Convert integers and numbers into the special number representations that ordinary base conversion leaves out — and back again. The graycode endpoint converts between an integer and its reflected binary Gray code, where consecutive values differ by exactly one bit (used in rotary encoders, Karnaugh maps and error reduction). The balanced-ternary endpoint converts between an integer and balanced ternary, the base-3 system with digits −1, 0 and +1 (written T, 0, 1) that needs no separate sign. The factoradic endpoint converts between an integer and the factorial number system (mixed radix 1, 2, 3, …), the basis of permutation ranking and Lehmer codes. The continued-fraction endpoint turns a fraction or a real number into its continued-fraction expansion [a0; a1, a2, …] and lists the convergents — the successively best rational approximations — and can rebuild the value from the terms. All integer maths is exact via big integers. Everything is computed locally and deterministically, so it is instant and private. Ideal for computer-science teaching, combinatorics and permutation ranking, error-correcting and encoder design, rational approximation, and recreational mathematics. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 5 endpoints. This handles special number representations; for ordinary base 2-36 conversion use a base-convert API.

Uptime

100.0%

Latency

74ms

Subs

3,396

Expand URI Templates (RFC 6570) — the standard used by GitHub, OpenAPI/Swagger, HAL and many hypermedia APIs — to build URLs from a template and a set of variables. The expand endpoint takes a template such as /users/{user}{?page,per_page} and a JSON object of variables, and returns the finished URI with everything correctly percent-encoded. It implements all four levels of the spec: simple expansion {var}; reserved {+var} and fragment {#var} expansion; the label {.var}, path {/var}, path-style-parameter {;var}, query {?var} and query-continuation {&var} operators; multiple variables {x,y}; and the value modifiers — prefix {var:3} (first N characters) and explode {var*} (expand lists and maps element by element). Variables can be strings, lists or associative maps. The parse endpoint inspects a template and lists its expressions, operators and variable names. Everything is computed locally and deterministically, so it is instant and private. Ideal for REST and hypermedia clients, API SDKs and code generators, OpenAPI tooling, and link building. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This expands URI templates; for building or parsing query strings use a query-string API and for canonicalising URLs use a URL API.

Uptime

100.0%

Latency

81ms

Subs

3,084

Non-cryptographic hash functions — the fast hashes used in hash tables, bloom filters, sharding, deduplication and cache keys. Give it text (UTF-8) or raw bytes as hex and it returns the digest under every algorithm at once, or under one named algorithm: FNV-1 and FNV-1a (32- and 64-bit), djb2, sdbm, Jenkins one-at-a-time, CRC-16 (CCITT-FALSE and ARC/IBM), Fletcher-16 and Fletcher-32, and MurmurHash3 (x86 32-bit, with an optional seed). Each digest is returned in hex and as an unsigned integer. Everything is computed locally and deterministically, so the same input always maps to the same hash — exactly what you need for stable bucketing and lookups. These are deliberately NOT for security: they are fast and well-distributed, not collision-resistant. Ideal for hash-table and bloom-filter implementations, consistent sharding and partitioning, cache and dedup keys, A/B bucketing, and teaching how hashing works. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. For cryptographic hashes (SHA, MD5, HMAC) use a hash API, and for CRC-32/Adler-32 integrity checksums use a checksum API.

Uptime

100.0%

Latency

82ms

Subs

3,193

Work with polynomials: find their roots, evaluate them, differentiate and integrate, and add, subtract, multiply or divide them. The roots endpoint returns every root — real and complex — using the exact quadratic formula for degree 2 and the Durand-Kerner method for higher degrees, with a clean list of just the real roots too. The evaluate endpoint computes p(x) and p'(x) at a point by Horner's method. The derivative endpoint returns the coefficients of the derivative and of the indefinite integral. The operate endpoint does polynomial arithmetic — addition, subtraction, multiplication, and long division giving a quotient and a remainder. Coefficients are given highest-degree first, so [1,-3,2] means x² − 3x + 2. Everything is computed locally and deterministically, so it is instant and private. Ideal for engineering and control systems, signal processing and filter design, computer graphics and curve fitting, scientific computing, and teaching algebra and calculus. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 5 endpoints. This is polynomial maths; for matrices and linear systems use a matrix API, for vectors a vector API, and for general arithmetic a math API.

Uptime

100.0%

Latency

72ms

Subs

3,128

Linear algebra as an API: multiply matrices, analyse a matrix, and solve linear systems — all computed locally and exactly. The multiply endpoint returns the product A×B, checking that the inner dimensions match. The analyze endpoint takes any matrix and returns its transpose and rank, and for square matrices also the determinant, trace, whether it is symmetric and invertible, and the inverse when it exists — using LU decomposition with partial pivoting and Gauss-Jordan elimination for numerical stability. The solve endpoint solves a system Ax = b for a square coefficient matrix by Gaussian elimination with partial pivoting, and reports cleanly when the matrix is singular and there is no unique solution. Matrices are passed as JSON arrays of rows, for example [[1,2],[3,4]]. Everything is deterministic and instant. Ideal for data-science and machine-learning prep, computer graphics and 3D transforms, engineering and physics, computer-vision calibration, control systems, and teaching linear algebra. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. This is matrix and linear-algebra maths; for 3D rotations use a quaternion API, for vector maths use a vector API, and for statistics use a stats API.

Uptime

100.0%

Latency

76ms

Subs

3,154

3D rotation maths as an API: convert freely between quaternions, Euler angles, axis-angle and rotation matrices, compose rotations, rotate vectors, and interpolate. The convert endpoint takes any one representation — a quaternion {w,x,y,z}, Euler angles (roll, pitch, yaw), an axis and angle, or a 3×3 matrix — and returns all four forms at once, normalized. The multiply endpoint composes two quaternions (the Hamilton product) so you can chain rotations. The rotate endpoint applies a quaternion to a 3D vector. The slerp endpoint does spherical linear interpolation between two orientations along the shortest path — the standard way to animate smooth rotations. Euler angles use the aerospace Z-Y-X (yaw-pitch-roll) intrinsic convention in degrees; quaternions follow the Hamilton convention with order w,x,y,z; matrices are row-major right-handed. Everything is computed locally and deterministically, so it is instant and private. Ideal for game and graphics engines, robotics and drones, IMU and sensor fusion, aerospace and flight dynamics, VR/AR, and 3D content tooling. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 5 endpoints. This is 3D rotation maths; for 2D geometry use a geometry API and for plain angle-unit conversion use an angle API.

Uptime

100.0%

Latency

76ms

Subs

3,042

Read and write resistor colour codes and snap values to the standard E-series. The decode endpoint takes the colour bands of a 3-, 4-, 5- or 6-band resistor and returns the resistance in ohms (nicely formatted as Ω/kΩ/MΩ/GΩ), the significant digits and multiplier, the tolerance, the minimum and maximum resistance that tolerance implies, and — for 6-band parts — the temperature coefficient in ppm/K. The encode endpoint goes the other way: give it a resistance in ohms (and optionally a band count and tolerance) and it returns the colour bands, picking the nearest value representable with the available significant digits. The eseries endpoint snaps any value to the nearest preferred resistor value in the E6, E12, E24, E48 or E96 series and reports the percentage error and the neighbouring preferred values. It uses the standard IEC 60062 colour assignments (including gold ×0.1 and silver ×0.01 multipliers and the implicit ±20% of a 3-band part). Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics design, PCB and BOM work, lab and hobby bench use, repair and reverse-engineering, and teaching. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. This is for resistor colour codes; for general number formatting use a number-format API.

Uptime

100.0%

Latency

76ms

Subs

4,743

Evaluate boolean-logic expressions and generate complete truth tables. The table endpoint takes a boolean expression, finds its variables, builds every row of the truth table (the first variable is the most-significant bit, the standard convention), and returns each row's values and result, the list of minterms (the row indices where the expression is true), a classification of tautology / contradiction / contingency, and a canonical sum-of-products (SOP) form. The evaluate endpoint computes the expression's value for one specific assignment of its variables. It understands the full set of operators in both symbol and word form — NOT (!, ~, ¬), AND (&, &&, ∧, *, ., AND), OR (|, ||, ∨, +, OR), XOR (^, ⊕), NAND, NOR, XNOR, implication (->, =>, →, IMPLIES) and the biconditional (<->, <=>, ↔, IFF) — with the usual precedence (NOT > AND > XOR > OR > IMPLIES > IFF), parentheses, and the constants 0/1 and true/false. Everything is computed locally and deterministically, so it is instant and private. Ideal for digital-logic and discrete-math teaching, hardware and HDL design, simplifying conditions in code, SAT-style sanity checks, and interview prep. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This evaluates boolean logic and builds truth tables; for arithmetic and equations use a math API.

Uptime

100.0%

Latency

76ms

Subs

3,803

Encode and decode CBOR (RFC 8949, Concise Binary Object Representation) — the IETF-standard binary data format behind COSE, WebAuthn/FIDO2, the EU Digital COVID Certificate, and many IoT and constrained-device protocols. The encode endpoint turns a JSON value into compact, definite-length CBOR, choosing the smallest head for each integer, string, array and map; the decode endpoint parses CBOR back into a JSON value. It implements the spec across all major types — unsigned and negative integers of every width, byte and text strings (including indefinite-length chunked strings), arrays, maps, tags, the simple values false/true/null, and half-, single- and double-precision floats — and rejects trailing or truncated data rather than silently mangling it. Byte strings and any non-UTF-8 text come back losslessly as {"_bytes_hex":"…"}, tags as {"_tag":{"tag":N,"value":…}}, non-finite floats as {"_float":"NaN|Infinity|-Infinity"}, and other simple values as {"_simple":N}, so encode and decode round-trip exactly. Bytes are exchanged as both hex and base64 so they survive any transport. Everything is computed locally and deterministically, so it is instant and private. Ideal for debugging CBOR, COSE and WebAuthn payloads, bridging JSON and CBOR systems, IoT and smart-card pipelines, and teaching the format. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is CBOR specifically; for MessagePack use the MessagePack API, for BitTorrent's Bencode use the Bencode API, for JSON, YAML, TOML or XML use those format APIs, and for base64, hex, URL or HTML encoding use a general encoding API.

Uptime

100.0%

Latency

79ms

Subs

4,335

Encode and decode MessagePack — the compact binary serialization format ("it's like JSON, but fast and small") used by Redis, Fluentd, many RPC systems and IoT protocols. The encode endpoint turns a JSON value into MessagePack bytes, automatically choosing the smallest representation for each integer, string, array and map; the decode endpoint parses MessagePack back into a JSON value. It implements the full spec — nil, booleans, every fixed and variable integer width, float32 and float64, str and bin, arrays and maps, and the ext family — and rejects trailing or truncated data rather than silently mangling it. Binary (bin) values and any non-UTF-8 string come back losslessly as a {"_bytes_hex":"…"} object, and ext values as {"_ext":{"type":N,"hex":"…"}}, so encode and decode round-trip exactly. Bytes are exchanged as both hex and base64 so they survive any transport. Everything is computed locally and deterministically, so it is instant and private. Ideal for debugging MessagePack payloads, bridging JSON and msgpack systems, RPC and cache tooling, IoT pipelines, and teaching the format. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is MessagePack specifically; for JSON, YAML, TOML or XML use those format APIs, for BitTorrent's Bencode use the Bencode API, and for base64, hex, URL or HTML encoding use a general encoding API.

Uptime

100.0%

Latency

80ms

Subs

3,183

Encode and decode Bencode (BEP 3) — the serialization format BitTorrent uses for .torrent metainfo files and tracker responses. The encode endpoint turns a JSON value into Bencode: objects become dictionaries with their keys sorted in raw byte order exactly as the spec demands, arrays become lists, whole numbers become integers, and strings become length-prefixed byte strings. The decode endpoint parses Bencode back into a JSON value and enforces the spec strictly — no leading zeros in integers, no negative zero, dictionary keys must be sorted and unique, and no trailing data is tolerated — so malformed input is rejected rather than silently mangled. Binary byte strings that are not valid UTF-8 are represented losslessly as a {"_bytes_hex":"…"} object, so encode and decode round-trip exactly even for the binary "pieces" field of a real torrent. Decode accepts the data either as text or, for genuinely binary payloads, as hex; encode returns both the Bencode text (when printable) and its hex bytes. Everything is computed locally and deterministically, so it is instant and private. Ideal for building and parsing .torrent files, tracker tooling, BitTorrent clients and DHT messages, and teaching how the format works. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is BitTorrent's Bencode specifically; for base64, hex, URL or HTML encoding use a general encoding API, and for JSON, YAML, TOML or XML use those format APIs.

Uptime

100.0%

Latency

78ms

Subs

4,713

Encode and decode Base45 (RFC 9285) — the compact binary-to-text encoding designed to pack densely into the alphanumeric mode of QR codes, best known as the carrier for the EU Digital COVID Certificate. The encode endpoint turns text (UTF-8) or raw bytes given as hex into a Base45 string; the decode endpoint turns a Base45 string back into bytes, returned as hex and — when the bytes are valid UTF-8 — as text. It uses the official 45-character alphabet (0-9, A-Z and a handful of symbols), packs two bytes into three characters (or one byte into two), and validates length and value ranges strictly so malformed input is rejected rather than silently mangled. Everything is computed locally and deterministically, so it is instant and private. Ideal for QR-code payloads, digital health and travel certificates, alphanumeric-mode encoders, and any binary data that must survive an uppercase-only channel. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is Base45 specifically; for base64, base32, hex, URL or HTML entity encoding use a general encoding API.

Uptime

100.0%

Latency

80ms

Subs

3,079

The email and MIME text encodings that general base64/hex toolkits leave out. The quoted-printable endpoint encodes and decodes Quoted-Printable (RFC 2045) — the Content-Transfer-Encoding that keeps mostly-ASCII text readable while escaping everything else as =XX hex, with the soft line-wrapping at 76 columns and trailing-whitespace handling the spec requires. The encoded-word endpoint encodes and decodes RFC 2047 encoded-words — the =?UTF-8?Q?…?= and =?UTF-8?B?…?= form used to carry non-ASCII text in email Subject, From, To and other headers — in either the Q (quoted-printable-style) or B (base64) variant, and decodes any mix of them back to plain text. Everything is UTF-8 and computed locally and deterministically, so it is instant and private. Ideal for building and parsing email (SMTP/IMAP), .eml and MIME tooling, newsletter and transactional-mail systems, and migrating legacy mail data. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. These are the MIME-specific encodings; for base64, base32, hex, URL and HTML entity encoding use a general encoding API.

Uptime

100.0%

Latency

83ms

Subs

4,163

Work out tips and split a bill — with exact cent maths so the per-person amounts always add back up to the total, no penny ever lost to rounding. The calc endpoint takes a bill, a tip percentage (15% by default) and a number of people and returns the tip amount, the grand total, the per-person amount, the effective tip percentage, and — when you want a tidy number — an optional rounding of the total either up to the next whole unit or to the nearest. When the bill does not divide evenly it produces a fair share list where a few people pay one cent more, so the parts sum precisely. The split endpoint divides any amount, optionally adding a tip first, evenly among people and returns that exact per-person share list. Everything is computed in integer cents locally and deterministically, so it is instant, private and always balances. Currency-agnostic — the numbers work for any currency. Ideal for restaurant and POS apps, expense-sharing and group-payment tools, delivery and service apps, and everyday bill splitting. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This calculates tips and splits; for percentage maths in general use a percentage API and for invoicing margins use a margin API.

Uptime

100.0%

Latency

84ms

Subs

4,075