CO2 Offset API vs GridVigil API

Two free Environment APIs compared on access, reliability and developer ratings, using data from our daily health checks.

The verdict

Choose CO2 Offset API if its data fits your use case better; on access and reliability it's level with GridVigil API.
Choose GridVigil API if you want to call it from browser JavaScript.

	CO2 Offset API	GridVigil API
What it does	API calculates and validates the carbon footprint.	Pressure scores, demand, generation mix and alerts for the 10 major U.S. power grids.
Provider	Corrently IO	GridVigil
API key	Not needed	Not needed
HTTPS	Yes	Yes
CORS (browser calls)	Unknown	Yes
Status today	Online · 1414 ms	Online · 1588 ms
Uptime (30 days)	Up	Up
Developer rating	Not rated yet	Not rated yet
Price	Free / free tier	Free / free tier

API calculates and validates the carbon footprint.

Service Rahmenwerk zur Bestimmung, Berichterstattung und Kompensation der Treibhausgasemissionen für...

Strengths

Pressure scores, demand, generation mix and alerts for the 10 major U.S. power grids.

GridVigil's free Developer API: one normalized JSON schema across every grid it tracks, with example requests and responses.

Strengths

Prototyping or a tutorial? Pick the one that needs no API key (both qualify).
Calling from a web page? You need CORS. Otherwise route requests through your own server or a serverless function.
Going to production? Favour HTTPS, a strong uptime record and a provider with clear rate limits and terms. Check each API's docs before you commit.
Still unsure? Both are free to try: send one request to each and compare the data you get back.

Neither needs an API key; you can call both straight away.

GridVigil API supports CORS, so front-end JavaScript can call it directly. Call the other from a server.