Bun vs Deno vs Node.js in 2026: benchmarks, trade-offs, and honest picks
Three viable JavaScript runtimes, each with a strong argument. After running all three in production, here's when we reach for each one - and when it genuinely doesn't matter.
The JavaScript runtime landscape in 2026 is genuinely competitive for the first time in fifteen years. Node.js is no longer the default assumption - Bun and Deno have both reached production maturity, have large enough ecosystems to rely on, and offer meaningful trade-offs worth understanding before you pick one for a new project. Here's our honest read after shipping production workloads on all three.
The benchmark picture
Raw benchmarks put Bun at roughly 14,000 requests per second on a basic HTTP workload - about 2.7x faster than Node.js and 2.3x faster than Deno on the same test. Cold start times tell a similar story: Bun clocks in at ~31ms versus Node's ~142ms, which matters most for serverless and edge deployments where functions spin up from cold frequently. These numbers are real, but they're also the ceiling of what benchmarks tell you - read times for production workloads are shaped by database latency, not runtime throughput.
# Rough HTTP throughput comparison (wrk, simple JSON response)
# Bun 1.x: ~14,300 req/s
# Deno 2.x: ~6,200 req/s
# Node.js 22: ~5,250 req/s
# Cold start (serverless-style spin-up)
# Bun: ~31ms
# Deno: ~55ms
# Node: ~142msWhen to pick Bun
Bun wins on raw performance and ships a batteries-included toolchain: built-in bundler, test runner, package manager, and SQLite driver. For greenfield APIs, CLI tools, and serverless functions where cold start latency directly affects user-perceived performance, Bun is the right pick. It also consumes roughly 40% less RAM than Node for the same workload, which matters on constrained infrastructure. The trade-off: the ecosystem is younger, and niche Node.js packages that depend on native bindings occasionally need workarounds.
When to pick Deno
Deno's value proposition is security-by-default and TypeScript-native execution. Scripts run with zero filesystem or network access unless you explicitly grant permissions - a meaningful property for running untrusted code, build scripts, or anything where least-privilege matters. Deno Deploy is the most ergonomic path to running TypeScript on the edge: the same code that runs locally runs in 30+ datacenters globally with no Docker config. If your team is TypeScript-first and values the security model, Deno is the most opinionated and coherent runtime for that context.
When to pick Node.js
Node.js is still the right default for teams inheriting existing codebases, for any project with deep native module dependencies, and for enterprise contexts where long-term support and ecosystem stability carry more weight than benchmark numbers. Node 22 ships with native TypeScript stripping support and has closed most of the ergonomic gaps that made Bun and Deno appealing as fresh-start alternatives. The ecosystem breadth is unmatched, and for most production workloads the runtime is fast enough that it's not the bottleneck.
The honest take
- For new serverless functions and edge workers: Bun, for cold start and throughput.
- For TypeScript-first services where security posture matters: Deno, for permissions model and first-class TS.
- For anything with existing Node.js dependencies, native modules, or a large team that doesn't want to retrain: Node.js 22, which is better than it's gotten credit for.
- Don't migrate an existing working service for runtime bragging rights - the performance ceiling for most apps is the database, not the runtime.
Written by Appesto Engineering.