Environment — entry 016 of 18
SustainMetrics
SustainMetrics provides a REST lookup over 18,000+ official GHG emission factors (UK DEFRA, US EPA, French ADEME, and Ember's global electricity data) for scope 1/2/3 carbon accounting. The underlying calculator is free to use in the browser with no signup, while the /api/v1 developer endpoint requires an X-API-Key from a paid plan starting at $29/month.
AuthenticationAPI KeySign up with the provider to obtain credentials.
HTTPSSupportedTraffic is encrypted in transit.
CORSEnabledCallable directly from browser JavaScript.
PricingFreemiumA usable free tier exists, with paid plans for more volume.
FormatsJSONResponses can be requested as JSON.
GreatAPIs Score
Score75
Authentication15/25API key required
Pricing17/20Freemium tier available
Docs14/20Documentation URL provided
Formats9/15Single response format
Freshness20/20Verified within 6 months
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<a href="https://greatapis.com/api/sustainmetrics/"><img src="https://greatapis.com/badge/sustainmetrics.svg" alt="Scored 75 on greatapis.com"></a>Auth quickstart
- Sign up with the provider to get an API key.
- Send it on every request as a header
Authorization: <key> - The exact header isn't documented — Authorization is a common default; confirm in the provider's docs.
Stored keyNo key stored
Your key is stored only in this browser (localStorage) and sent directly to the API — never to greatapis.