API
Global warming potentials from an API — IPCC AR6 and AR5, each returned with its assessment-report citation and data version. Convert any gas to CO₂e with a sourced coefficient.
curl https://api.greencalculus.com/v1/factors/gwp.CH4_fossil.ar6_100 \
-H "Authorization: Bearer YOUR_KEY"IPCC_AR6 version 2026.203Get a free API key Read the docs →
?as_of= re-resolves any version our archive holds.mcp.greencalculus.com.Sign up for a free API key at greencalculus.com/developers, then call the endpoint shown above with your key as a bearer token. The free tier includes 1,000 calls a month, no card required.
Yes. Every response returns its exact source reference, licence and data version, so you can cite the exact figure and reproduce it in an audit. A saved response is self-contained — it carries the value and the version it used, so it reproduces indefinitely without us. The as_of parameter re-resolves a past version from our archive, which begins 10 August 2026 and deepens with every release.
29.8, sourced to IPCC_AR6 (data version 2026.203). The API always returns the current value with its full provenance.
Free for 1,000 calls a month, no card, and commercial use is permitted with attribution. The Developer plan is $49/month for 50,000 calls. Business is $299/month and adds what the lower tiers do not include: redistribution rights, the bulk corpus feed pre-filtered to everything you may lawfully republish, 500,000 calls, and change webhooks. The credit stays on every tier except Enterprise, which is the only plan that may remove it.
Yes. The same sourced data is available over the Model Context Protocol at mcp.greencalculus.com, so an AI agent can pull cited numbers directly instead of guessing.