Bun vs. Deno vs. Node.js in 2026: what real benchmarks show
Re-benchmarked on one machine, Bun, Deno and Node.js results overturn many recycled numbers online. Here's which runtime fits which use case in 2026.
An engineer re-ran Bun 1.3.14, Deno 2.9.1, and Node.js 24.18.0 on the same 12-core Linux box, pinning a minimal JSON endpoint to a single core. The first pass revealed that a JavaScript-based load generator (autocannon) was itself the bottleneck; switching to the Rust-based oha nearly doubled the measured throughput for Bun and Deno. As a result, even the commonly cited 'Bun > Deno > Node' ordering didn't hold: on current versions, Deno topped the chart at 133,000 requests/sec versus Bun's 122,000, while Node trailed at 47,000.
Many other widely repeated figures — cold start times, install speed, JSON parsing, and test runner performance — also turned out to be inflated. Bun's supposed 35x install speed advantage over npm shrinks to roughly 2-12x once numbers are properly scaled, and Deno's test runner, often claimed to be 2-3x faster than Jest, was actually slower on a suite of trivial tests. The author lists four red flags for spotting similarly inflated benchmarks: near-identical results across different systems, load testers written in the same language as the target, missing version numbers, and tables stitched from mismatched sources.
The practical takeaway: all three runtimes are production-ready in 2026, and the right choice depends on project constraints rather than benchmark headlines. Node.js remains the safe default where maximum ecosystem compatibility matters; Bun suits new projects prioritizing developer experience and speed; Deno now leads in raw throughput while offering the most security-first, TypeScript-native experience. In serverless and edge environments, these cold-start differences translate directly into cost, making the runtime choice a meaningful engineering decision.