O11y toolkit
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/metrics lint

This tool enables you to validate the format of Prometheus metrics, and make sure they can be scraped by a Prometheus server.

Prometheus supports two exposition formats: the Prometheus text-based exposition format and OpenMetrics. The text-based exposition format is widespread, and many applications and client libraries supports it. Additionally, it can be used from scripts, to push metrics to the Pushgateway or written to *.prom files, to be collected by the textfile collectors (available in both the Node Exporter and the Windows Exporter).

Our toolkit also provides oy-expose, a standalone tool that can expose the metrics of a file to be consumed by Prometheus.


To use this tool, simply paste the content of your *.prom file, the body of your Pushgateway request, or the output of a /metrics HTTP endpoint in the following text area. Then, click on the “Lint” button.

You can click on the following button to load a few metrics:

Security and privacy

The input is parsed in your browser and is not sent to our servers. This tool is based on the official client_golang library and is cross compiled to WASM, so that it runs natively in your browser.

Format specification

This tool uses the Prometheus text-based exposition format. OpenMetrics is not supported yet.

Everything is run locally from your browser, we do not receive or collect your metrics.

Command line tool

This utilise behaves like the promtool check metrics command, which is downloadable with Prometheus.

Metrics validation

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