Free open data APIs compared
Encyclopedias, statistics, earthquakes, holidays, energy and more. Ranked by measured 7-day uptime, then speed. Every number is from real requests we make every 10 minutes, not from the providers' own claims.
On the last 26 checks, Nager.Date Holidays leads on both reliability (100.00% uptime) and speed (96 ms median from Sweden).
| # | API | Now | Uptime 7d | p50 24h | p95 24h |
|---|---|---|---|---|---|
| 1 | Nager.Date Holidays list of US holidays | Operational | 100.00% | 96 ms | 305 ms |
| 2 | USGS Earthquakes GeoJSON FeatureCollection | Operational | 100.00% | 154 ms | 650 ms |
| 3 | World Bank Indicators Brazil is BRA | Operational | 100.00% | 161 ms | 342 ms |
| 4 | Wikipedia REST summary title is Earth | Operational | 100.00% | 187 ms | 266 ms |
| 5 | UK Carbon Intensity data[0].intensity present | Operational | 100.00% | 346 ms | 1767 ms |
| 6 | Where the ISS at? ISS position in valid range | Operational | 100.00% | 855 ms | 1459 ms |
| 7 | Open Library Search numFound > 0 | Slow | 100.00% | 1174 ms | 3536 ms |
Latency is measured from a single server in Sweden including DNS and TLS. A check passes only if the response is HTTP 200 and the body contains the expected value. Live page, updated every 10 minutes.
Try them
Nager.Date Holidays docs
curl -s "https://date.nager.at/api/v3/PublicHolidays/2026/US"
USGS Earthquakes docs
curl -s "https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/all_hour.geojson"
World Bank Indicators docs
curl -s "https://api.worldbank.org/v2/country/br?format=json"
Wikipedia REST docs
curl -s "https://en.wikipedia.org/api/rest_v1/page/summary/Earth"
UK Carbon Intensity docs
curl -s "https://api.carbonintensity.org.uk/intensity"
Where the ISS at? docs
curl -s "https://api.wheretheiss.at/v1/satellites/25544"
Open Library Search docs
curl -s "https://openlibrary.org/search.json?q=dune&limit=1"
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