Steady-state heat loss
API · /uvalue-api
U-Value & R-Value API
healthy
4,531 Subscribers
Building-fabric thermal maths — U-value, R-value and heat loss — as an API, computed locally and deterministically. The rvalue endpoint takes a wall, roof or floor build-up as a list of layers (each given as a thickness and a thermal conductivity, or a thickness and a named material from a built-in table, or a direct R-value) and adds the interior and exterior surface resistances to return the total thermal resistance R = Rsi + ΣR_layer + Rse and the thermal transmittance U = 1/R, in both metric (RSI, m²K/W and W/m²K) and imperial (R-value) units, with a per-layer breakdown. The layer endpoint gives the R-value of a single material from its thickness and conductivity, R = thickness/conductivity, and solves for whichever of the three you leave out, with conductivities for concrete, brick, timber, plasterboard, mineral wool, EPS, XPS, PIR and more. The heatloss endpoint computes the steady-state heat loss through an element, Q = U·A·ΔT, in watts, BTU per hour and kWh per day from a U-value (or R-value), an area and a temperature difference (direct or as indoor minus outdoor), and an annual figure from heating degree days. Everything is computed locally and deterministically, so it is instant and private. Ideal for building-energy and retrofit tools, architecture and construction apps, insulation and SAP/Passivhaus calculators, and energy-assessment software. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is building-fabric thermal performance; for rule-of-thumb HVAC equipment sizing use an HVAC API.
api.oanor.com/uvalue-api
API health
healthy- Uptime
- 100.00%
- Server probes · 24h
- Avg latency
- 80 ms
- Server probes · 24h
- Subscribers
- 4,531
- active
- Total calls
- 76
- last 7 days
Pricing
Pick a tier — billed monthly, cancel anytime.
Free
Free
- 2,000 calls / month
- 2 requests / second
- Hard cap (429 above quota, no overage)
- U-value & R-value for single assemblies
- Metric & imperial (RSI) units
- 2 req/s for prototyping
- Community support
Starter
€9.00 /month
- 15,000 calls / month
- 6 requests / second
- Hard cap (429 above quota, no overage)
- Multi-layer wall, roof & floor assemblies
- Total U-factor + heat-loss output
- ASHRAE material-conductivity library
- Email support
Pro
€24.00 /month
- 80,000 calls / month
- 15 requests / second
- Hard cap (429 above quota, no overage)
- Surface-resistance & air-gap modelling
- Batch assembly evaluation
- Compliance-ready U-value reports
- Priority support
Mega
€69.00 /month
- 400,000 calls / month
- 40 requests / second
- Hard cap (429 above quota, no overage)
- High-volume CAD/BIM & estimator integration
- Full ASHRAE + custom material catalogues
- 99.9% uptime SLA
- Dedicated engineering support
Built by
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Live continuous front-month (1!) quotes for the major liquid futures across every asset class, with no key: precious & base metals (gold, silver, copper, platinum), energy (WTI crude, natural gas, gasoline, heating oil), grains (wheat, corn, soybeans), softs (coffee, sugar, cocoa, cotton), livestock, equity-index (E-mini S&P 500, Nasdaq, Dow, Russell), interest-rate (2/5/10/30-year Treasuries) and FX futures from COMEX, NYMEX, CBOT, CME, CME_MINI and ICE US. Get a per-contract quote by short code (GC, CL, ES, ZW) with last price, % change and intraday OHLC, a full cross-asset board, or a per-category cut — a curated board of the contracts that actually trade.
api.oanor.com/cmefutures-api
Commodity Movers & Performance API
What is moving across the commodity complex right now, computed live from Yahoo Finance futures (no key, nothing stored). Just as stock, FX and crypto traders watch the day's biggest gainers and losers, commodity traders want the same board for energy, metals, grains, softs and livestock. For every commodity this measures the change on the day, the week and the month, the day's high and low, the 52-week high and low and where the price sits in that 52-week range. The movers endpoint returns the whole complex ranked by daily change — the top gainers and losers — plus the weekly and monthly leaders, and can be filtered to one sector. The commodity endpoint returns one commodity's full performance card. The commodities endpoint lists what is covered. The commodity movers / performance-board cut — distinct from the commodity-momentum API (which ranks by a blended multi-month momentum factor and trend regime), the commodity-price feed, the commodity-spreads and the seasonality APIs. It answers what moved today, across the complex.
api.oanor.com/commoditymovers-api
Commodity Seasonality API
The calendar patterns commodity traders position around, computed live from ~10 years of Yahoo Finance monthly futures data (no key, nothing stored). Commodities are the most seasonal market there is: natural gas tends to rally into winter heating demand, gasoline into the summer driving season, grains around the planting and harvest calendar. This measures it directly — for each commodity it takes a decade of monthly returns, groups them by calendar month, and returns the average return in each of the twelve months, the share of years that month was positive (the win rate), and the historically strongest and weakest months. The seasonality endpoint returns one commodity's full 12-month seasonal profile plus the current month's historical bias. The month endpoint flips it around: for a given calendar month it ranks every commodity by its historical average return, so you can see what is seasonally bullish or bearish right now. The commodities endpoint lists what is covered. The commodity-seasonality / calendar-pattern cut — distinct from the FX-seasonality API (currencies), the commodity-price feed, the commodity-spreads and the commodity-momentum APIs. It answers what a commodity usually does this month, not what it costs today.
api.oanor.com/commodityseasonality-api
Commodities Momentum & Relative-Strength API
Which corner of the commodity complex is leading and which is lagging, ranked by trailing momentum, computed live from Yahoo Finance futures (no key, nothing stored). A price tells you where a commodity is; momentum tells you where the money is flowing. This scores every major commodity — crude, Brent, natural gas, gasoline and heating oil in energy; gold, silver, copper, platinum and palladium in metals; corn, wheat and soybeans in grains; coffee, sugar, cocoa, cotton and orange juice in softs; live cattle and lean hogs in livestock — by its return over five horizons (1 week, 1 month, 3 months, 6 months and a ~1-year proxy), blends them into a single momentum score and ranks the whole complex into leaders and laggards. The screener endpoint returns that ranked table with a relative-strength rank and trend regime for each. The momentum endpoint drills into one commodity: its multi-horizon returns, where it sits versus its 50- and 200-day averages, and a trend label. The commodities endpoint lists what is covered. The cross-commodity momentum / relative-strength factor cut — distinct from the commodity-price feed (front-month prices), the commodity-spreads API (crack/crush/ratios) and the precious-metals spot API. It answers what is leading the complex, not what one thing costs.
api.oanor.com/commoditymomentum-api
Frequently asked questions
Quick answers about pricing, quotas, and integration.
How do I get an API key for U-Value & R-Value API?
Sign up for free at oanor.com, generate an API key from the developer dashboard, and call U-Value & R-Value API with the x-oanor-key header. No credit card needed for the free tier.
What's the rate limit for U-Value & R-Value API?
Free tier allows 1 request per second. Paid plans scale up to 50 requests per second on the Mega tier. Hard limits return HTTP 429 above the quota — no surprise overage charges.
How much does U-Value & R-Value API cost?
U-Value & R-Value API has a free tier with 100 calls / month. Paid plans start at €9.00 / month with higher quotas and faster rate limits.
Can I cancel my subscription anytime?
Yes. Plans are billed monthly and you can cancel anytime from your billing dashboard. No long-term contracts and no cancellation fee.
Is U-Value & R-Value API GDPR-compliant?
All requests to U-Value & R-Value API go through our EU-based gateway. Your upstream API key never leaves our server and no personal data is shared with the upstream provider beyond the request you send.
Pick an endpoint from the list on the left to see its details and try it.
Code snippets
Sign up to get an API key, then call any path under your slug.
curl https://api.oanor.com/uvalue-api/SOME_PATH \
-H "x-oanor-key: oanor_test_..."const res = await fetch("https://api.oanor.com/uvalue-api/SOME_PATH", {
headers: { "x-oanor-key": "oanor_test_..." }
});
const data = await res.json();$ch = curl_init("https://api.oanor.com/uvalue-api/SOME_PATH");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-oanor-key: oanor_test_..."]);
$response = curl_exec($ch);import requests
r = requests.get(
"https://api.oanor.com/uvalue-api/SOME_PATH",
headers={"x-oanor-key": "oanor_test_..."},
)
print(r.json())Ratings
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