Tomorrow

Overview

Tomorrow.io’s Weather API provides current conditions, forecasts, real-time weather alerts, and historical data via a key-based REST API — with a strong focus on granular, minute-level data and developer-friendly tooling. Free tier available for evaluation and light apps.

Quick Start

Current weather (replace YOUR_KEY):

curl "https://api.tomorrow.io/v4/timelines?location=paris&apikey=YOUR_KEY" \
  -H "Accept: application/json"

Timeline with specific fields:

curl "https://api.tomorrow.io/v4/timelines?location=48.85,2.35&fields=temperature,precipitationProbability&timesteps=1h&units=metric&apikey=YOUR_KEY"

Weather alerts:

curl "https://api.tomorrow.io/v4/timelines?location=paris&fields=weatherCode&timesteps=current&apikey=YOUR_KEY&alerts=true"

Authentication

• Register at tomorrow.io (free) → create an API key in the dashboard.
• Send it as the apikey query parameter (an invalid key returns 401 — verified).

Rate Limits & Notes

• Free tier: 500 requests/day (with limited historical depth); paid plans scale.
• The API v4 uses timelines with fields, timesteps (current/1h/1d), and units.
• location accepts a place name or lat,lon; apikey is the query param (not a header).
• Alerts and minute-level forecasts are included on the free tier for current timesteps.

FAQ

Is Tomorrow.io free? Yes — free tier 500 requests/day; paid plans scale up.

How do I get a key? Register at tomorrow.io, then create an API key in the dashboard.

Is it easy to switch from another weather API? The timelines model is similar to most v4 weather APIs — field-based selection makes it straightforward.