OpenWeather (OpenWeatherMap) is the most popular weather API — current conditions, forecasts and historical data — with a free tier big enough for many apps and low-cost paid plans above it. Here's what it costs and how to get your key.
| Piano | Price / month | Calls | Meglio per |
|---|---|---|---|
| Gratuito più economico | €0 | ~1,000 / day (60/min, ~1M/mo) | Hobby apps, dashboards |
| Startup | €35 | 600/min, 10M/mo | Growing usage |
| Sviluppatore | €160 | 3,000/min, 100M/mo | Production |
| Professional | €410 | 30,000/min, 1B/mo | High-volume apps |
| Expert | €1,200 | 100,000/min, 3B/mo | Su larga scala |
| One Call by Call (3.0/4.0) | first 1,000/day free | then €0.0014/call | Forecast + history |
→ Bundling several APIs? Total them on the Calcolatore dei costi dello stack API.
OpenWeather's free tier gives about 1,000 calls a day (60/min) for current weather and short forecasts — plenty for a hobby app or dashboard — and you only need an email to get a key. Heavier use or premium data (long history, minute forecasts) moves you to a paid monthly tier or the metered One Call product.
1. Iscriviti a openweathermap.org.
2. Tuo Chiave API is under My API keys — copy it (it can take a little while to activate).
3. Call endpoints with appid=YOUR_KEY.
4. Subscribe to One Call (OpenWeather now recommends 4.0 for new integrations; 3.0 still works but is being phased out) or a paid monthly tier for advanced data.
Test it with a simple request:
WeatherAPI.com E Tomorrow.io are popular rivals with free tiers; Open-Meteo is fully free and needs no key for non-commercial use; national services (NWS) are free where available.
OpenWeather's free tier is generous for a weather API: around 60 calls per minute with a monthly cap near 1,000,000 calls on the classic current-weather and forecast products. One Call (3.0 or the newer, recommended 4.0) is metered separately under the "One Call by Call" subscription, with a default free allowance of 1,000 calls per day that you can raise (with billing enabled) by setting your own daily limit.
Paid monthly tiers scale the per-minute rate sharply while keeping the same endpoints (billed in EUR):
Go over your allowance and OpenWeather returns an HTTP 429 (and may temporarily block the key), so cache results and respect the per-minute rate. If you are checking OpenWeather API rate limits before launch, note the split model: the classic API is limited by calls-per-minute plus a monthly cap, while One Call is billed and capped per day.
See our other data-API guides to compare free monthly quotas before committing a production app to a single weather provider.
Yes — the free tier gives roughly 1,000 calls a day for current weather and basic forecasts, with just an email to sign up.
Either pay-as-you-go per call (One Call, €0.0014/call after the first 1,000/day free) or a fixed monthly tier like Developer (€160/mo) for higher limits and more endpoints. Note OpenWeather bills in EUR, not USD.
Sign up at openweathermap.org and copy the key from 'My API keys' — allow some time for it to activate.
Open-Meteo is free and keyless for non-commercial use; WeatherAPI.com also has a free tier.
Not affiliated with OpenWeather. Prices are reference estimates — always verify on the official pricing page.