Air & water quality monitoring · OpenAQ (nonprofit)

OpenAQ

Nonprofit that aggregates open government and low-cost-sensor air quality data worldwide into one free API.

OpenAQ is a nonprofit that harmonizes air quality measurements published by government agencies, research networks and low-cost sensor projects (including PurpleAir and Clarity feeds) into a single open data platform. It covers pollutants such as PM2.5, PM10, NO2, SO2, O3 and CO from tens of thousands of stations in over 100 countries, at whatever cadence the source publishes, from near-real-time hourly government feeds to daily aggregates from smaller networks; resolution and reliability therefore vary by source and are documented per station. Data is free to query through a public API and downloadable bulk archives, with no login required for basic use. OpenAQ is funded by grants and philanthropic donors rather than data sales, and its code and datasets are openly licensed.

At a glance

Vendor OpenAQ (nonprofit)
Pricing model Open source + paid options
Free tier Yes
Deployment Cloud
Open source Yes (MIT)
Best for Researchers, journalists and developers who need one free, global API for air quality data instead of stitching together national sources.

Pricing

Free public API and open data archives; funded by grants and donations, not subscriptions.

Pricing has not been verified yet — see the vendor's site.

Features

  • Aggregated government and low-cost sensor data
  • 100+ countries, tens of thousands of stations
  • Free public REST API
  • Bulk historical data archives
  • PM2.5, PM10, NO2, SO2, O3, CO coverage
  • Per-station metadata on source and instrument type
  • Open-source platform code

Integrations

Profile last reviewed September 21, 2026

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