JetStream 3 is a new browser benchmark developed collaboratively by Google, Apple, Mozilla, and other partners, replacing JetStream 2 from 2019. It focuses on computationally intensive web workloads including browser games, physics simulations, cryptography, and complex algorithms. A major update is the expanded WebAssembly coverage: 12 new Wasm workloads now cover toolchains including Rust, Kotlin/Wasm, Dart2wasm, J2CL, and .NET, with Wasm making up 15-20% of the suite (up from 7%). New JavaScript workloads cover real-world use cases like React SSR, TypeScript compilation, Babylon.js, Three.js, and MobX startup performance. The benchmark is designed to run in engine shells like V8's d8 for faster iteration, and uses a consensus governance model across all major browser vendors.
Table of contents
Why Do We Benchmark, Anyway?Driven by Open GovernanceRipe for an UpdateJetStream vs. Other BenchmarksHow We Select WorkloadsRethinking WebAssemblyThe New WebAssembly WorkloadsThe New and Updated JavaScript WorkloadsUpdated JavaScript WorkloadsConclusionSort: