Grafana k6
Developer-first load testing: JavaScript scripts, Go engine, CI-native thresholds.
What it is
k6 scripts are JavaScript but execute on a Go runtime, giving a familiar authoring language with far better resource efficiency than JVM- or Python-based generators. Thresholds let a test fail the build on p95 latency or error rate, which is what makes it usable as a regression gate rather than an occasional exercise. Grafana Cloud k6 adds distributed execution and dashboards.
Best for
Where it is strong
- Excellent resource efficiency — thousands of virtual users from one modest machine.
- Thresholds make performance a build gate rather than a report nobody reads.
- Native Grafana and Prometheus integration ties load results to server-side metrics.
Where it falls short
- The JavaScript runtime is not Node — no npm modules unless bundled, which surprises people.
- Browser-level load testing exists but is much heavier and less mature than protocol-level testing.
- Distributed execution requires either the cloud product or your own orchestration.
Pricing
From $19 per month (Grafana Cloud Pro platform fee; k6 usage is billed on top)
Free tierFree tier: The k6 CLI is fully open source with no virtual-user limits when self-run.
What drives the bill: Self-hosted is free and unlimited. On Grafana Cloud the free tier includes 500 virtual-user-hours a month, then k6 bills from $0.150 per virtual-user-hour on top of the $19 Pro platform fee — the VU-hours, not the platform fee, are where budgets go.
Check current pricing on Grafana Labs’s siteFigures are indicative and were last reviewed August 2026. Vendors change pricing often; confirm before you commit.
Works with
What people who use Grafana k6 say
No reviews of Grafana k6 yet. If you have used it in anger, yours would be the first.
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