HTTP Clients (Server-side)

Built-in / native

• ★ fetch — built into Node 18+, Bun, Deno, Workers, browsers. The default.
• undici — Node's fetch is built on this; you can use it directly for Pool, Agent, mocking, retry interceptors. The default for performance-sensitive Node code.
• Bun's fetch — drop-in compatible, very fast.
• Request / Response / Headers — standard now; same code works on Node + Workers + Deno.

Lightweight wrappers around fetch

• ★ ofetch (UnJS) — auto-JSON, retries, hooks, error class with data, query helpers. Used by Nuxt / Nitro; works everywhere fetch does. Default if you want a tiny ergonomic wrapper.
• ★ ky — promise-based, retries, hooks, timeouts, instances. Default if you've used axios and want lighter.
• redaxios — axios API in 800 bytes via fetch.
• wretch — chainable fetch wrapper.

Heavier / older

• axios — still huge install base; bigger bundle; use ky / ofetch for new code.
• got — Node-only, very feature-rich (timeouts, hooks, streams, retries); heavier than ofetch.
• node-fetch — pre-built-in-fetch era; mostly retired.
• request — deprecated; do not use.

Specialized

• gRPC clients — @grpc/grpc-js (Node), nice-grpc, connect-rpc (HTTP+gRPC bridge).
• WebSocket clients — ws (Node), built-in WebSocket (browsers / Workers / Bun / Deno).
• Server-Sent Events — built-in EventSource; eventsource-parser for streaming LLM responses.
• GraphQL clients — see Data Fetching.

Mocking / testing

• ★ MSW (Mock Service Worker) — intercept fetch in tests / dev / Storybook with the same mocks. Default.
• nock — older; Node-specific HTTP interceptor.
• undici's MockAgent — built-in for undici / Node fetch.
• Polly.js — record / replay HTTP.

Generated clients (typed from spec)

• openapi-fetch + openapi-typescript — typed fetch from any OpenAPI.
• Hey API — full TS clients from OpenAPI; see OpenAPI Tooling.
• GraphQL Code Generator — typed GraphQL clients.
• gql.tada — type-safe GraphQL via type-only inference.

Pick this if…

• Default new code: fetch directly, or ofetch / ky for ergonomics.
• Performance-sensitive Node: undici directly.
• Migrating off axios: ky.
• Typed client from a third-party API: openapi-fetch + openapi-typescript.
• Mocking in tests: MSW.