Bun vs Node.js vs Deno — Runtime Comparison 2026

In this tutorial, you'll learn about Bun vs Node.js vs Deno. We cover key concepts, practical examples, and best practices to help you understand and apply this topic effectively.

Bun prioritizes raw speed with JavaScriptCore, Node.js offers unmatched ecosystem maturity with npm, and Deno provides secure-by-default TypeScript — three runtimes with fundamentally different design philosophies.

At a Glance

Key Differences

• Performance: Bun leads in HTTP throughput (2-3x more req/s than Node.js) and startup time (50ms vs 300ms). Its JavaScriptCore engine and Zig implementation give it the edge for I/O-bound workloads. Deno sits between Node.js and Bun in most benchmarks.
• TypeScript support: Deno runs TypeScript natively with zero configuration. Bun also supports TypeScript natively using a built-in Transpiler. Node.js requires third-party tools like ts-node or tsx. Node.js 22+ has experimental TypeScript stripping via --experimental-strip-types.
• Security model: Deno is the only runtime with a permission system — scripts need explicit --allow-read, --allow-net, --allow-env flags. Node.js and Bun give full system access by default.
• Ecosystem: Node.js has npm with 2M+ packages and every major framework targets it. Deno can import npm packages via npm: specifier. Bun supports npm packages natively and its bun install is 10-30x faster than npm install.

When to Choose Each

Node.js is the safest choice for production. It powers most JavaScript backends, has the largest ecosystem, and is supported by every cloud provider. Choose Node.js for enterprise APIs, Serverless functions, and teams that prioritize stability over speed.

Deno is ideal for new TypeScript-first projects. Its web-standard APIs (fetch, Request, Response), no-config TypeScript, and permission sandboxing make it productive and secure. Choose Deno for CLI tools, scripts, and teams that want modern defaults.

Bun is the fastest runtime and keeps getting faster. Its built-in test runner, bundler, and package manager simplify the toolchain. Choose Bun for high-throughput HTTP services, fast CI/CD, and projects where startup time or throughput matters most.

Side by Side: HTTP Server Performance

Node.js

import { createServer } from "node:http";
const server = createServer((req, res) => {
  res.writeHead(200, { "Content-Type": "text/plain" });
  res.end("Hello from Node.js");
});
server.listen(3000, () => console.log("Node:3000"));

Deno

Deno.serve((req: Request) => {
  return new Response("Hello from Deno", {
    headers: { "Content-Type": "text/plain" },
  });
});

Bun

Bun.serve({
  port: 3000,
  fetch(req) { return new Response("Hello from Bun"); },
});

# Install a simple HTTP benchmark tool
npm install -g autocannon

# Benchmark all three
autocannon http://localhost:3000 -c 100 -d 10

Expected approximate benchmark results:

Node.js: 70k req/s, latency p99 ~25ms
Deno:    90k req/s, latency p99 ~18ms
Bun:     200k req/s, latency p99 ~8ms

flowchart TD
    A["Choose a Runtime"] --> B{"Need max\nperformance?"}
    B -->|Yes| C["Bun\nFastest HTTP\nFastest startup"]
    B -->|No| D{"Need TypeScript\nwithout config?"}
    D -->|Yes| E["Deno\nNative TS\nSecure by default"]
    D -->|No| F{"Need npm\necosystem?"}
    F -->|Yes| G["Node.js\n2M+ packages\nProduction proven"]
    F -->|No| C
    style C fill:#fef3c7,stroke:#d97706
    style E fill:#bbf7d0,stroke:#16a34a
    style G fill:#dbeafe,stroke:#2563eb

Side by Side: File Read

// Node.js
import { readFile } from "node:fs/promises";
const data = await readFile("threats.json", "utf-8");
console.log(JSON.parse(data).length, "threats loaded");

// Deno
const data = await Deno.readTextFile("threats.json");
console.log(JSON.parse(data).length, "threats loaded");

// Bun
const data = await Bun.file("threats.json").text();
console.log(JSON.parse(data).length, "threats loaded");

Expected output (all three):

1042 threats loaded

FAQ

{{< faq "Which is fastest, Bun, Node.js, or Deno?">}} Bun is the fastest in HTTP benchmarks (~2-3x more req/s than Node.js) and has the fastest startup time (~50ms vs ~300ms). For real-world apps, database and network I/O are usually the bottleneck, reducing the practical difference. {{< /faq >}}

{{< faq "Should I migrate from Node.js to Bun or Deno?">}} Migrate existing projects only if you have a specific performance need (Bun) or want better security and TypeScript support (Deno). For new projects, consider Bun for speed-critical apps or Deno for security-conscious TypeScript projects. For most teams, Node.js remains the pragmatic default. {{< /faq >}}

Related Comparisons

TypeScript vs JavaScript — Express vs Fastify — pnpm vs npm vs Yarn — Webpack vs Vite

Built by the developers of Doda Browser, DodaZIP, and Durga Antivirus Pro. Updated 2026-06-24.