// JavaScript Runtime Comparison 2025
Complete Bun.js vs Node.js comparison: startup time, HTTP throughput, memory, npm compatibility, TypeScript support, and when each runtime wins. Updated for 2025.
| Feature | Bun | Node.js | Winner |
|---|
Benchmarks below are representative figures from published comparisons (Strapi, Builder.io, official Bun benchmarks). Real-world results vary by workload, OS, and application code.
tsc, no ts-node, no @swc/core. bun run file.ts just works. Built-in bundler (faster than esbuild in benchmarks), test runner, and package manager. One tool replaces npm/yarn, Webpack/esbuild, and ts-node. This significantly simplifies project setup.--experimental-strip-types for TypeScript. But the standard setup still requires ts-node, tsc, or an external bundler. The ecosystem around Node.js tooling (Vite, esbuild, SWC, Webpack) is mature, well-documented, and has massive community support. More configuration, but also more flexibility.bun install is ~25x faster than npm install. Implements Node.js core APIs (fs, path, http, crypto). However, packages with native addons (.node binaries), some platform-specific internals, or Electron dependencies may not work. Bun's Node.js compatibility improves with every release.Use Bun when:
You're starting a new project and want TypeScript without configuration. You're building CLI tools where startup speed matters. You're writing scripts and utilities that run frequently. You want a single tool (bundler + package manager + test runner + runtime) to replace multiple. You're building serverless functions where cold start time is billed. Your team is comfortable being on a newer, faster-moving runtime.
Use Node.js when:
Your project uses native Node.js addons (.node files) that haven't been ported. You need maximum production stability for a high-traffic application. Your stack depends on packages that are untested with Bun. You're working in an environment where only Node.js is supported (some cloud providers, Docker images). Your team has deep Node.js expertise and operational tooling already configured.
The honest answer for 2025:
For new projects with standard npm dependencies, Bun is a legitimate choice — especially if TypeScript, speed, or tooling simplicity matter. For existing Node.js applications, the migration cost rarely justifies the performance gain unless startup time is a specific bottleneck. For enterprise applications with complex native dependencies or strict SLA requirements, Node.js remains the safer default.
bun install. Packages using native addons (.node binaries compiled for Node.js) may not work. Very low-level libuv internals may behave differently. Bun's compatibility list grows with each release. Most common packages — Express, Fastify, Prisma, Drizzle, React, Next.js — work on Bun.bun run file.ts runs TypeScript directly — no tsc, ts-node, or @swc/core required. Bun also has a built-in bundler that supports TypeScript, JSX, and TSX. Node.js 22+ has experimental TypeScript stripping via --experimental-strip-types, but full native TypeScript support in Node.js is not yet stable. This is one of Bun's clearest advantages for TypeScript-heavy projects.bun install reads package.json and installs from the npm registry, ~25x faster than npm install. CommonJS (require()) and ESM (import) both work. The node_modules folder structure is the same. Most packages that work on Node.js work on Bun without code changes. Check Bun's compatibility tracker at bun.sh for specific package status.