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    Tools & Data Sources · Glossary

    Real User Monitoring (RUM)

    Matt SuffolettoWritten by Matt Suffoletto
    Published June 26, 2026
    Real User Monitoring
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    TL;DR

    Real User Monitoring (RUM) is the practice of collecting performance data, including Core Web Vitals, from a JavaScript snippet that runs in the browsers of actual visitors and reports back to an analytics endpoint.

    What is Real User Monitoring (RUM)?

    Real User Monitoring (RUM) is the practice of collecting performance data, including Core Web Vitals, from a JavaScript snippet that runs in the browsers of actual visitors and reports back to an analytics endpoint.

    Learn more in our RUM vs CrUX: choosing data sources guide, or work with us through our done-for-you speed optimization service.

    How RUM is Measured

    RUM is implemented through the web-vitals JavaScript library or commercial tools such as SpeedCurve, Akamai mPulse, and DebugBear.

    Related Terms

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