22 Free APIs Every Developer Should Bookmark in 2026 — No Credit Card, No Catch

I spent the last month testing free tiers of every major developer API. Not the "free trial for 14 days" kind. The actually-free, no-credit-card, use-it-in-production kind. Here are 22 APIs that are genuinely free, with enough quota to build real apps. Databases MongoDB Atlas — Free 512MB Cloud Database 512MB storage, full MongoDB API, Atlas Search, Charts. Shared cluster on AWS/GCP/Azure. Never expires. Neon — Free Serverless Postgres 512MB Postgres with git-like branching, auto-scaling to zero, serverless driver for edge functions. PlanetScale — Serverless MySQL MySQL with schema branching and zero-downtime migrations. Built on Vitess (same tech as YouTube). Scaler plan from $39/mo. Supabase — Free Postgres + Auth + Storage Full backend: Postgres database, authentication, file storage, real-time subscriptions, edge functions. 500MB database, 1GB file storage. Firebase — Free Backend Suite Firestore, Realtime Database, Authentication, Hosting, Cloud Functions, Storage. 1GB Firestore,