JetStream 2

On the record

Benchmark size

JetStream 2.2 has 64 subtests.browserbench.org · read 12 Oct 2026

Browser stability

The maker reports measuring JetStream 2.2 scores in Chrome, Safari, and Firefox and finding them as stable as JetStream 2.1.webkit.org · read 12 Oct 2026

Changes in 2.2

JetStream 2.2 runs the same benchmarks as 2.1 and includes fixes for minor issues, including timer resolution and segmentation subtests.browserbench.org · read 11 Oct 2026

CLI or automation

Yesbrowserbench.org · read 22 Sep 2026

Command line

The maker says JetStream 2.2 includes fixes for command-line scripts used with D8 and SpiderMonkey shells.browserbench.org · read 12 Oct 2026

JavaScript scoring

Most JavaScript benchmarks score startup, worst-case, and average-case performance equally.browserbench.org · read 11 Oct 2026

Overall score

The suite combines benchmark scores using a geometric mean, with each benchmark weighted equally.browserbench.org · read 11 Oct 2026

Purpose

JetStream 2.2 is a JavaScript and WebAssembly benchmark suite focused on advanced web applications.browserbench.org · read 12 Oct 2026

Score limitation

Scores from JetStream 2.2 are not comparable to scores from other versions of JetStream.browserbench.org · read 12 Oct 2026

Scoring

It combines individual benchmark scores using a geometric mean, with each benchmark weighted equally.browserbench.org · read 12 Oct 2026

Subtests

JetStream 2.2 has 64 subtests, including a JavaScript implementation of a GPU shading language benchmark called WSL.browserbench.org · read 11 Oct 2026

Version changes

JetStream 2.2 runs the same benchmarks as 2.1 and fixes several issues, including timer resolution and task queue race conditions.browserbench.org · read 12 Oct 2026

Version limitation

Scores from JetStream 2.2 are not comparable with scores from other JetStream benchmark versions.browserbench.org · read 11 Oct 2026

WebAssembly scoring

WebAssembly benchmark scores weigh startup time and total execution time equally.browserbench.org · read 11 Oct 2026

What it measures

It rewards browsers that start up quickly, execute code quickly, and run smoothly.browserbench.org · read 12 Oct 2026

Workload areas

JavaScript,WebAssembly,Web Workers,Promises,async iteration,Unicode regular expressions,JavaScript parsing,simulationsbrowserbench.org · read 22 Sep 2026

Workloads

Its benchmarks cover WebAssembly, Web Workers, Promises, async iteration, Unicode regular expressions, and JavaScript parsing.browserbench.org · read 12 Oct 2026

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