5 Free APIs Every Developer Should Bookmark in 2026

Every side project needs APIs — for geo data, prices, screenshots, DNS lookups, or running untrusted code. Most API providers make you jump through hoops: email verification, credit cards, OAuth flows, rate limit walls. Here are 5 APIs I've been using that give you a free key instantly (one curl call, no signup) and actually work. 1. IP Geolocation API Turn any IP address into a location — city, country, coordinates, timezone, ISP. curl "https://agent-gateway-kappa.vercel.app/api/geo/8.8.8.8" \ -H "X-API-Key: YOUR_KEY" { "ip" : "8.8.8.8" , "city" : "Mountain View" , "region" : "California" , "country" : "US" , "loc" : "37.4056,-122.0775" , "org" : "AS15169 Google LLC" , "timezone" : "America/Los_Angeles" } Use cases : visitor analytics, fraud detection, content localization, access control by country. // Detect visitor country and redirect const res = await fetch ( `https://agent-gateway-kappa.vercel.app/api/geo/ ${ userIP } ` , { headers : { " X-API-Key " : API_KEY } }); const { count