API marketplace

Fetch any URL and analyse its HTTP response security headers — grading the site A+ to F the way securityheaders.com and Mozilla Observatory do. Pass a URL and the service makes the request server-side (following redirects), then reports which protective headers are present, which are missing (with concrete remediation advice) and which response headers leak information. Graded headers include Strict-Transport-Security (HSTS), Content-Security-Policy, X-Content-Type-Options, X-Frame-Options, Referrer-Policy, Permissions-Policy and Cross-Origin-Opener-Policy; information-leak headers include Server and X-Powered-By. A companion endpoint returns every raw response header. Private and internal targets are refused (SSRF-guarded). Built for security audits, CI/CD security gates, attack-surface reviews and compliance checks. A security-header grader — distinct from the SSL/TLS certificate check (sslcheck), host reachability (hostcheck), the IANA HTTP status-code reference (http) and the on-page SEO audit (seo). No upstream key, no cache.

Uptime

100.0%

Latency

98ms

Subs

3,524

Look up the live Tor network as an API — powered by the Tor Project's official Onionoo service and the canonical bulk exit-node list. Check whether any IPv4 or IPv6 address is a Tor relay (is_tor_relay) and whether it is an exit node that clients leave the network through (is_exit_node, corroborated against the bulk exit list), returning the full matching relay record(s): nickname, fingerprint, flags, country, autonomous system, advertised bandwidth, exit-policy summary and first/last-seen dates. Or search the public relay list by nickname, fingerprint, IP, country or flag (Exit, Guard, Fast, Stable…) with paging. Built for fraud and abuse triage, login-risk scoring, comment- and registration-filtering, and network research — knowing at a glance whether a connection originates from the Tor network. Range data is fetched live from the Tor Project, so it is always current. A Tor-network lookup — distinct from cloud/CDN attribution (cloudips), IP geolocation (ipgeo), ASN/BGP ownership (asn, ripestat) and open-port exposure (internetdb). No upstream key, no cache.

Uptime

100.0%

Latency

409ms

Subs

3,654

Attribute any IP address to the cloud provider, CDN, region and service that owns it — from the official, publicly-published IP-range lists of AWS, Google Cloud, Cloudflare, Oracle Cloud (OCI), Fastly and GitHub. Pass an IPv4 or IPv6 address and get every matching prefix with its provider, region/scope and service, plus an is_cloud flag that tells you at a glance whether the address belongs to a known cloud or CDN — or list a single provider's published ranges, filtered by region, service and IP version. Built for firewall allow-lists, abuse and fraud triage, bot and egress classification, SSRF defence and knowing whether inbound or outbound traffic originates from a cloud or CDN. Range data is fetched live from each provider's canonical public list, so it is always current. A cloud/CDN IP-attribution service — distinct from IP geolocation (ipgeo), ASN/BGP ownership (asn, ripestat), open-port exposure (internetdb) and the IANA port/protocol registries (netports, ipprotocols). No upstream key, no cache.

Uptime

100.0%

Latency

197ms

Subs

3,922

Reference genome assemblies as an API — powered by NCBI Assembly, the registry of genome builds for organisms across the tree of life. Search assemblies by organism (or free text) and look up any assembly's metadata: its accession (GCF_… RefSeq or GCA_… GenBank), name (e.g. GRCh38.p14), organism and taxon id, assembly level (complete genome, chromosome, scaffold or contig), contiguity statistics (contig and scaffold N50), sequencing coverage, RefSeq category, UCSC and Ensembl names, the submitting organization, release date and FTP download paths. From the human reference genome to any sequenced microbe, plant or animal, it turns the genome-assembly registry into a clean search-and-fetch API. A genome-assembly registry — distinct from sequence (ENA), genome annotation (Ensembl), variant (ClinVar, dbVar) and gene-expression (GEO) databases. Open data from NCBI Assembly (public domain).

Uptime

100.0%

Latency

614ms

Subs

4,993

The classical-music repertoire as an API — powered by Open Opus, an open catalogue of classical composers and their works. Search composers by name or browse them by musical epoch (Medieval, Renaissance, Baroque, Classical, Romantic and beyond), getting each composer's full name, epoch and birth/death years; then list a composer's works, optionally filtered by genre — orchestral, chamber, keyboard, stage, vocal or opera. From Bach and Mozart to Beethoven's 44 orchestral works, it turns the canon of classical music into a clean search-and-browse API. A classical-music repertoire reference — distinct from commercial music catalogues of tracks, artists and albums. Ideal for classical-music, education, concert-programming, streaming and media applications. Open data from Open Opus (CC-BY-SA / CC0).

Uptime

100.0%

Latency

401ms

Subs

3,611

Functional-genomics experiments as an API — powered by NCBI GEO (Gene Expression Omnibus), the largest public repository of gene-expression data. GEO archives expression series and curated datasets from microarray and high-throughput-sequencing experiments across every organism. Search experiments by keyword and optionally by organism, and look up any series or dataset to get its metadata: title, summary, assay type (expression profiling by array or by sequencing), organism, number of samples, platform and the publication behind it. From β-cell stress studies to cancer transcriptomics across human and mouse, it turns the GEO archive into a simple search-and-fetch API for transcriptomics, bioinformatics and research-data discovery. A gene-expression / functional-genomics dataset repository — distinct from sequence (ENA), variant (ClinVar, dbVar), structure (PDB) and ontology databases. Open data from NCBI GEO (public domain).

Uptime

100.0%

Latency

654ms

Subs

4,943

Human genomic structural variation as an API — powered by NCBI dbVar, the archive of structural variants (SVs): copy-number variants (CNVs), large deletions, duplications, insertions, inversions and translocations, typically larger than 50 base pairs. This is the structural counterpart to single-nucleotide variant databases: search structural variants overlapping a gene (or by free text) and get each variant's dbVar accession, the study it came from, its type, the genes it overlaps, its genomic placement on GRCh38 and its clinical significance; then look up any variant for the full record — placements on both GRCh37 and GRCh38 assemblies, variant type, genes, clinical significance, study type, methods and variant counts. From BRCA1 CNVs to Cri-du-chat deletions, it is ideal for genomics, cytogenetics, rare-disease and bioinformatics work. A structural-variation / CNV resource — distinct from clinical single-nucleotide variant interpretation (ClinVar), population allele frequencies (gnomAD) and trait associations (GWAS). Open data from NCBI dbVar (public domain).

Uptime

100.0%

Latency

583ms

Subs

3,231

Discover the funding and projects behind research — as an API over OpenAIRE, the open research graph that links scholarly outputs to the grants and funders that paid for them. Search funded research projects (grants) by keyword and filter by funder — the European Commission, NIH, NSF, UKRI, DFG, Wellcome and many more — and get each project's title, grant code, acronym, funder, start and end dates, funded amount and summary. Search publications too, with their title, authors, year, DOI, type, publisher, open-access status and whether they were publicly funded. It is the place to find research grants and the money behind science — ideal for research-funding discovery, science-policy analysis, grant intelligence, reporting and open-science tooling. A research-funding / projects resource — distinct from DOI registries (Crossref, DataCite) and scholarly-metadata indexes (OpenAlex). Open data from OpenAIRE (CC BY).

Uptime

100.0%

Latency

382ms

Subs

3,175

Solar irradiance and agroclimatology for any location on Earth — as an API over NASA POWER (Prediction Of Worldwide Energy Resources), derived from NASA satellite and reanalysis data. Get the solar resource needed to size and assess PV and CSP systems: global (GHI), direct-normal (DNI) and diffuse horizontal irradiance, clear-sky irradiance and the clearness index — either as long-term monthly climatology normals for quick site assessment, or as a daily time series for a date range (1981-present). The same call also serves meteorology — temperature, wind speed, relative humidity and precipitation — making it ideal for solar energy, agriculture, building-energy modelling and climate work. From cloudy Berlin to the Sahara, it turns a coordinate into bankable solar and climate data. A solar-resource / agroclimatology data source — distinct from PV-system energy simulation (PVGIS) and historical-weather records. Open data from NASA POWER.

Uptime

100.0%

Latency

753ms

Subs

4,916

Long-term climate projections as an API — daily, downscaled output from high-resolution CMIP6 global climate models for any location on Earth, from 1950 all the way to 2050. See how temperature, precipitation, wind and humidity are projected to change under a warming climate: get the daily projection over any date range (choose your variables and climate model), or per-year aggregates — annual mean temperature and total precipitation — that reveal the warming trend at a place over the coming decades. Seven HighResMIP models are available (EC_Earth3P_HR, MPI_ESM1_2_XR, MRI_AGCM3_2_S, CMCC_CM2_VHR4 and more). From planning and agriculture to risk assessment, sustainability and climate research, it turns climate-model data into a simple coordinate-in, projection-out call. A climate-projection resource — distinct from real-time weather forecasts, historical weather observations and Köppen climate classification. Open data from Open-Meteo (CC BY 4.0), based on the CMIP6 HighResMIP ensemble.

Uptime

100.0%

Latency

598ms

Subs

3,756

Map projections and coordinate reference systems as an API — the EPSG dataset made queryable. Every CRS, from geographic systems like WGS 84 (the GPS standard, EPSG 4326) to projected ones like Web Mercator (3857), the UTM zones and national grids, has an EPSG code. Search the dataset by name to find the code you need, then resolve any code to its full definition: name, kind (geographic, projected, …), area of use, scope, and — most usefully — the ready-to-paste PROJ.4 string and WKT definition that GIS libraries (GDAL, PROJ, PostGIS, Leaflet, OpenLayers, QGIS, GeoPandas) consume directly. Search comes from the official EPSG Registry maintained by IOGP; the PROJ.4/WKT exports come from epsg.io. A geodesy / coordinate-reference-system resource — distinct from geocoding (addresses to coordinates), geohashing and administrative-boundary APIs. Ideal for GIS, mapping, surveying, remote-sensing and spatial-data applications.

Uptime

100.0%

Latency

485ms

Subs

3,984

See what any host exposes to the internet — as an API over Shodan's free InternetDB. Give it an IPv4/IPv6 address (or a hostname, which is resolved to its IP) and get that host's attack surface: the open ports (annotated with common service names), the products and technologies detected on it (CPEs), its reverse hostnames, Shodan's classification tags, and the known vulnerabilities (CVE identifiers) observed on its services. A dedicated vulnerabilities view returns just the CVEs and whether the host appears vulnerable. It is fast, requires no key, and is built for security, asset-discovery, external attack-surface monitoring and reconnaissance workflows. A network-exposure / attack-surface resource — distinct from IP geolocation (where an address is), the IANA port registry (what a port number means) and CVE databases (what a vulnerability is). Data from Shodan InternetDB (free / non-commercial use).

Uptime

100.0%

Latency

101ms

Subs

4,516

Web-page time travel as an API — powered by the Internet Archive's Wayback Machine, the archive of hundreds of billions of captured web pages going back to 1996. Given any URL, find out whether it has been archived and get the snapshot closest to now, the snapshot closest to a specific date (true time-travel: see a page as it looked on, say, 1 January 2010), or the very oldest capture on record — each with its exact capture timestamp and a direct link to the archived copy. It is the go-to tool for detecting and recovering from link rot, citing sources that may change or disappear, checking when a page was first archived, and digital-preservation, research and journalism workflows. A web-archival / link-rot resource — distinct from the Internet Archive's media-item library (books, audio and video). Data from the Internet Archive Wayback Machine.

Uptime

87.5%

Latency

1297ms

Subs

3,139

Check whether a password has appeared in known data breaches — as an API over Have I Been Pwned's Pwned Passwords corpus (800+ million unique compromised passwords). It uses k-anonymity: only the first 5 characters of a password's SHA-1 hash are ever sent upstream, so the password itself never leaves in full. Pass a password (hashed in memory, never stored or logged — send it via POST so it never appears in a URL/log) or a SHA-1 hash to learn whether it has been breached and how many times; or fetch a raw k-anonymity range for a 5-character hash prefix and do the matching entirely on your own side for zero password exposure. Screening sign-ups and password resets against breached-password lists is recommended by NIST 800-63b, and this makes it a one-call check. A breach / credential-security resource — distinct from password generators, cryptographic hashing and bcrypt. Open data from Have I Been Pwned (Troy Hunt), CC BY 4.0.

Uptime

100.0%

Latency

138ms

Subs

4,273

Protein-protein interaction networks as an API — powered by STRING, the database of known and predicted protein associations that combines evidence from laboratory experiments, curated pathway databases, gene co-expression, genomic context and automated text mining into a single confidence score, across thousands of organisms. Get a protein's top interaction partners (each with the combined confidence score and the seven evidence-channel subscores), the interaction network among any set of proteins as scored edges, and functional enrichment for a gene set — the over-represented GO terms, KEGG pathways, Pfam domains and more, each with its p-value, FDR and member genes. Pass gene symbols (TP53) or STRING/Ensembl ids, for human (default) or any species by NCBI taxon id. It is a cornerstone of systems biology — ideal for network analysis, functional genomics, pathway and bioinformatics tools. A protein-interaction-network resource — distinct from biological pathways (Reactome), curated protein complexes (Complex Portal) and Gene Ontology annotations (QuickGO). Open data from STRING (CC BY 4.0).

Uptime

100.0%

Latency

606ms

Subs

4,536

Polygenic (risk) scores as an API — powered by the NHGRI-EBI PGS Catalog, the open database of published polygenic scores: weighted combinations of genetic variants used to estimate a person's genetic predisposition to a trait or disease. Search traits by name to find their ontology ids, list every polygenic score developed for a trait, and read a score's full metadata — the reported and mapped (EFO/MONDO) traits, the number of variants in the score, the development method, genome build, the ancestry distribution of the samples it was built and evaluated on, the publication behind it (title, journal, date, PubMed id), the release date, license and a direct link to the scoring file. From breast cancer and coronary artery disease to type 2 diabetes and BMI, it is ideal for statistical genetics, genomics, risk-prediction research and bioinformatics tools. A polygenic-score / genetic-risk-prediction resource — distinct from single-variant association studies (GWAS Catalog), population allele frequencies (gnomAD) and clinical variant interpretation (ClinVar). Open data from the NHGRI-EBI PGS Catalog (CC BY 4.0).

Uptime

100.0%

Latency

227ms

Subs

4,398

The Jewish calendar as an API — powered by Hebcal. Convert any date between the Gregorian and Hebrew calendars (with the formatted Hebrew date and the Jewish events falling on that day), list the Jewish holidays of any year — major and minor festivals, Rosh Chodesh and special Shabbatot — each with its English and Hebrew name, date and category, and get this week's Shabbat candle-lighting time, Torah portion (parashah) and Havdalah time for any location by GeoNames id or coordinates. From Rosh Hashanah and Yom Kippur to Passover, Shavuot and Hanukkah, with Hebrew dates rendered in Hebrew script, it is ideal for calendar, scheduling, event, religious and cultural applications. A Jewish-calendar resource — distinct from secular public-holiday and Islamic prayer-time APIs. Open data from Hebcal (CC-BY 4.0 / GPL).

Uptime

100.0%

Latency

200ms

Subs

4,457

Real example sentences with human translations as an API — powered by Tatoeba, the large collaborative corpus of millions of sentences in hundreds of languages, each linked to translations contributed and reviewed by real people (not machine translation). Search for sentences containing a word or phrase in one language and get how they are actually translated into another — perfect for seeing a word "in the wild", building vocabulary and flashcards, or as a human-quality translation aid. Look up any sentence by id to get its full set of translations. From "good morning" in English to its German, French, Spanish, Japanese or Mandarin equivalents, across ISO-639-3 languages, it is ideal for language-learning, vocabulary, flashcard, dictionary-companion and linguistics applications. A human-translated example-sentence corpus — distinct from dictionaries (definitions), machine translation and word APIs. Open data from Tatoeba (CC-BY 2.0 FR / CC0).

Uptime

100.0%

Latency

814ms

Subs

4,409

Independent greenhouse-gas emissions data as an API — powered by Climate TRACE, the coalition (backed by Al Gore) that monitors global emissions from satellites, sensors and AI rather than self-reported figures. Get any country's emissions for a given year — CO2, methane (CH4) and nitrous oxide (N2O) in tonnes, plus CO2-equivalent over 100- and 20-year horizons — together with the country's global emissions rank and its share of total world emissions; pass several countries at once to compare them side by side. List the full set of sectors, subsectors and gases that Climate TRACE tracks (power, transportation, manufacturing, agriculture, fossil-fuel operations, waste and more). From China and the United States to any nation on Earth, with data from 2015 onward, it is ideal for climate, ESG, sustainability, policy, journalism and research applications. An independent emissions-inventory data source — distinct from electricity-grid carbon intensity, activity footprint calculators and climate classification. Open data from Climate TRACE (CC BY 4.0).

Uptime

100.0%

Latency

230ms

Subs

3,293

Gene function as an API — powered by EMBL-EBI's QuickGO and the Gene Ontology (GO), the standard vocabulary that describes what gene products do across three aspects: molecular function, biological process and cellular component. Given a gene or protein (a UniProt accession), list every GO annotation made for it — the GO term, its aspect, the qualifier, the evidence code, the supporting reference (e.g. a PubMed id), the organism and who assigned it — optionally filtered by aspect or organism. Look up any GO term to get its definition, aspect, synonyms and number of child terms; and search the ontology by name to find the right GO terms. GO term names are resolved automatically on annotations. From TP53 to any protein in any species, it is the backbone of functional genomics — ideal for enrichment analysis, annotation pipelines, bioinformatics and research tools. A gene-function annotation resource (which genes have which functions, with evidence) — distinct from generic ontology-term lookup. Open data from EMBL-EBI QuickGO and the GO Consortium (CC BY 4.0).

Uptime

100.0%

Latency

159ms

Subs

4,853

Every research organization in the world as an API — powered by ROR, the Research Organization Registry. ROR assigns a persistent open identifier (a ROR ID) to universities, government labs, companies, nonprofits, hospitals, archives and research facilities, with rich, curated metadata and crosswalks to GRID, ISNI, Wikidata and the Crossref Funder Registry. Search the registry by name (and filter by country or organization type); resolve any ROR ID to its full record — names, acronyms and aliases, types, location (city, country, coordinates), website, domains, external identifiers and relationships to parent and child organizations; and match a messy free-text affiliation string ("Dept. of Physics, Heidelberg University, Germany") to the most likely organizations with a confidence score — perfect for cleaning and disambiguating author-affiliation data. It is a research-organization identifier registry, distinct from a plain university directory, and a natural companion to ORCID (for people) in any scholarly-metadata stack. Open data from ROR (CC0).

Uptime

100.0%

Latency

212ms

Subs

4,335

Scholarly citations as open data — powered by OpenCitations (COCI), the open citation index. Unlike a metadata lookup, OpenCitations treats every citation as a first-class object: given a DOI you can list the papers that cite it (incoming citations) and the papers it references (outgoing), each annotated with its OpenCitations Identifier (OCI), the date the citation was created, the timespan between the two works, and whether it is a journal- or author-self-citation. Plus quick citation and reference counts for any DOI. It is built for citation-network and bibliometric work — research-impact analysis, self-citation detection, citation-timespan studies and science mapping — and is distinct from scholarly-metadata services (Crossref, OpenAlex). From a single paper to a whole reference graph, ideal for bibliometrics, research-analytics and reference-management tools. Open data from OpenCitations (CC0).

Uptime

100.0%

Latency

326ms

Subs

4,375

The tree of life as an API — powered by the Open Tree of Life, the project that unifies published phylogenetic trees and taxonomies into a single synthetic tree spanning about 2.3 million named species. Resolve any scientific name to its canonical taxon and Open Tree Taxonomy (OTT) id (cross-referenced to NCBI, GBIF and other sources); read a taxon's classification and full lineage of ancestors up the tree (genus, family, order, class, …); and compute the most recent common ancestor (MRCA) of any set of species — the heart of comparative biology and "how related are these organisms?" questions. From Homo sapiens and the great apes to any branch of plants, fungi, animals and microbes, it is ideal for biology, evolution, ecology, education and bioinformatics tools. An evolutionary-tree / phylogenetics reference — distinct from species-occurrence data (biodiversity / GBIF), marine taxonomy (WoRMS) and sequence databases. Open data from the Open Tree of Life project (CC0).

Uptime

100.0%

Latency

311ms

Subs

4,439

Human genetic trait associations as an API — powered by the NHGRI-EBI GWAS Catalog, the curated reference of published genome-wide association studies. It answers the core question of statistical genetics: which genetic variants (SNPs) are associated with which traits and diseases, and how strongly. Look up a SNP to get its functional class, genomic location and mapped genes; pull every trait association reported for it — the trait, p-value, effect size (odds ratio or beta), risk allele and frequency, and author-reported genes; and read the study behind the evidence — trait, sample sizes, ancestries, genotyping technology and the publication (PubMed id, authors, journal, date). From type 2 diabetes and Crohn disease to systemic lupus erythematosus and hundreds of thousands of associations, it is ideal for genomics, bioinformatics, statistical-genetics and biomedical research tools. A published genetic-association evidence base — distinct from population allele frequencies (gnomAD), clinical variant interpretation (ClinVar) and genome annotation (Ensembl). Open data from the NHGRI-EBI GWAS Catalog (EMBL-EBI).

Uptime

100.0%

Latency

319ms

Subs

3,590