What it does
Grafana k6 is a performance-testing tool that models virtual-user activity in JavaScript. The local CLI can execute a script against an application, while Grafana Cloud provides hosted test execution and results. A test author defines the target requests and load profile, then inspects response and performance measurements.
The local guide starts with a simple JavaScript script and runs it with the k6 command-line tool. Add the request and the virtual-user and duration settings that match the question you are asking, then compare results across runs. Treat a tutorial script as a starting point, not a production load profile: test only a target you are authorized to exercise and raise traffic gradually.
The k6 repository is AGPL-3.0 licensed. Grafana’s pricing page presents a no-cost Grafana Cloud tier that includes k6 performance tests and a paid tier with additional retention and usage-based pricing. Local CLI use and hosted execution are different operating modes, so account for the runner capacity and cloud usage separately.
Strengths
- The official guide shows a local JavaScript test workflow.
- The project offers both a CLI and a hosted Grafana Cloud performance-test path.
- The repository license is AGPL-3.0.
Watch out for
- A load test sends traffic to its target; test only systems you are authorized to exercise.
- Hosted usage and local runner capacity have different limits and cost considerations.
Best for
- Running repeatable HTTP load tests from JavaScript
- Measuring how an application behaves under a controlled virtual-user profile
Sources
- Running k6 | Grafana k6 documentation (Oct 25, 2026)
- grafana/k6 | GitHub (Oct 25, 2026)
- k6/LICENSE.md at master | GitHub (Oct 25, 2026)
- Grafana Pricing | Grafana Labs (Oct 25, 2026)