Environmental APIs provide data on air quality, pollution levels, carbon emissions, and ecological metrics. Build sustainability dashboards, environmental monitoring tools, or green energy applications.
| Name | Description | Auth | HTTPS | CORS | Status |
|---|---|---|---|---|---|
| BreezoMeter Pollen | Daily Forecast pollen conditions data for a specific location | apikey | Yes | unknown | unknown |
| Carbon Interface | API to calculate carbon (C02) emissions estimates for common C02 emitting activities | apikey | Yes | yes | unknown |
| Climatiq | Calculate the environmental footprint created by a broad range of emission-generating activities | apikey | Yes | yes | unknown |
| Cloverly | API calculates the impact of common carbon-intensive activities in real time | apikey | Yes | unknown | unknown |
| CO2 Offset | API calculates and validates the carbon footprint | none | Yes | unknown | unknown |
| IQAir | Air quality and weather data | apikey | Yes | unknown | unknown |
| Luchtmeetnet | Predicted and actual air quality components for The Netherlands (RIVM) | none | Yes | unknown | unknown |
| OpenAQ | Open air quality data | apikey | Yes | unknown | unknown |
| PM2.5 Open Data Portal | Open low-cost PM2.5 sensor data | none | Yes | unknown | unknown |
| PM25.in | Air quality of China | apikey | No | unknown | unknown |
| PVWatts | Energy production photovoltaic (PV) energy systems | apikey | Yes | unknown | unknown |
| Srp Energy | Hourly usage energy report for Srp customers | apikey | Yes | no | unknown |
| UK Carbon Intensity | The Official Carbon Intensity API for Great Britain developed by National Grid | none | Yes | unknown | unknown |
| Website Carbon | API to estimate the carbon footprint of loading web pages | none | Yes | unknown | unknown |
5 of these APIs require no authentication — you can start making requests immediately without signing up for an account. Just pick one from the table above, check its documentation, and send your first request.
9 APIs in this category require a free API key. This usually means creating a free account on the provider's website and copying your key from the dashboard. The process typically takes less than a minute.
Not sure where to start? Look for APIs marked as "alive" in the status column — these were recently verified as working. For browser-based projects, check that the API supports CORS.
Yes, all APIs listed on API Bouncer have a free tier. Some are completely open (no sign-up needed), while others require a free account to get an API key. Free tiers typically have rate limits — check each API's documentation for specifics.
It depends on your needs. Consider: Do you need authentication or prefer no-auth? Does your project need CORS support for browser access? How many requests will you make? Start with a no-auth API to prototype quickly, then switch to a more feature-rich option if needed.
We run periodic health checks on all listed APIs. The "Status" column shows whether each API was responding at our last check. APIs marked as "alive" were recently verified. You can also test any API yourself using curl or our guides on testing APIs.
Most free APIs allow commercial use, but terms vary by provider. Always check the specific API's terms of service. Some APIs have separate free and commercial tiers with different rate limits.
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