Metrics
Largest Contentful Paint
Largest Contentful Paint (LCP) measures loading performance. To provide a good user experience, LCP should occur within 2.5 seconds of when the page first starts loading.
Interaction to Next Paint
Interaction to Next Paint (INP) measures interactivity. To provide a good user experience, pages should have a INP of 200 milliseconds or less.
Cumulative Layout Shift
Cumulative Layout Shift (CLS): measures visual stability. To provide a good user experience, pages should maintain a CLS of 0.1. or less.
Open Source Real User Monitoring Tools
boomerang
End user oriented web performance testing and beaconing
boomcatch
A standalone, node.js-based beacon receiver for boomerang.
Basic RUM
Backoffice of Basic RUM which serves performance enthusiasts look at waterfall diagrams and generate some diagrams on their own.
apm-agent-rum-js
Elastic APM Real User Monitoring (RUM) JavaScript agent
mPulse.js
The mPulse JavaScript API (mpulse.js) allows you to send beacons from JavaScript to Akamai mPulse via the mPulse Beacon API.
OpenReplay
Session replay and product analytics you can self-host. Ideal for reproducing issues, co-browsing with users and optimizing your product.
Perfume.js
Web performance library for measuring all performance vitals metrics
rrweb
record and replay the web
Raygun
Monitor and improve front-end performance
sitespeed.io
sitespeed.io is an open-source tool for comprehensive web performance analysis, enabling you to test, monitor, and optimize your website’s speed using real browsers in various environments.
webperf-snippets
A curated list of snippets to get Web Performance metrics to use in the browser console or as snippets on Chrome DevTools.
Open Source Product Analytics Tools
Ackee
Self-hosted, Node.js based analytics tool for those who care about privacy.
chiffre
Privacy-first, end-to-end encrypted analytics
Counter
Web Analytics made simple
Countly
Countly is a product analytics platform that helps teams track, analyze and act-on their user actions and behaviour on mobile, web and desktop applications.
freshlytics
Open source privacy-friendly analytics
goatcounter
Easy web analytics. No tracking of personal data.
hypercable
Hypercable Analytics is a fully featured high performance scalable alternative to Google Analytics, build with timescaledb openresty redis and rails.
kindmetrics
Kind metrics analytics for your website
matomo
Empowering People Ethically with the leading open source alternative to Google Analytics that gives you full control over your data. Matomo lets you easily collect data from websites & apps and visualise this data and extract insights. Privacy is built-in. Liberating Web Analytics.
piratepx
Just a little analytics insight for your personal or indie project
Pirsch
Pirsch is a drop-in, server-side, no-cookie, and privacy-focused analytics solution for Go.
Plausible
Simple, open source, lightweight (< 1 KB) and privacy-friendly web analytics alternative to Google Analytics.
PostHog
PostHog provides open-source web & product analytics, session recording, feature flagging and A/B testing that you can self-host.
Shynet
Modern, privacy-friendly, and detailed web analytics that works without cookies or JS.
Umami
Umami is a simple, fast, privacy-focused alternative to Google Analytics.