How to Build a Free API with Cloudflare Workers (Zero Infrastructure Cost)

Running an API usually means paying for servers. But Cloudflare Workers lets you deploy production-ready APIs on a generous free tier: 100,000 requests per day, zero cold starts, and global edge deployment. Here's how to build one from scratch. What You Get for Free Cloudflare Workers free tier includes: 100,000 requests/day 10ms CPU time per request (enough for most APIs) KV Storage: 100,000 reads/day, 1,000 writes/day Global deployment across 300+ data centers Custom domains via Cloudflare DNS For personal projects, internal tools, and moderate-traffic APIs, this is more than enough. Setting Up Install Wrangler Wrangler is Cloudflare's CLI for Workers development. npm install -g wrangler wrangler login Create a New Project wrangler init my-api cd my-api This generates a basic project with wrangler.toml and src/index.js. Configure wrangler.toml name = "my-api" main = "src/index.js" compatibility_date = "2026-03-01" [vars] API_VERSION = "1.0.0" [[kv_namespaces]] binding = "CACHE" id =