Time to Interactive history for mobile and desktop

Deliver stellar experiences to everyone

Monitor and audit web performance.
Make meaningful improvements where it matters.

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The world’s best brands chose Calibre to be their performance companion

buzzfeed
ableton
mapbox
codepen
basecamp

newThird Party Tracking: Measure the impact of embedded JavaScript

Simulate real-world conditions

Understand what your audience is experiencing. Choose from global test locations, turn off ads or mimic mobile devices effortlessly.

Learn about your users

Stay on track with budgets

Spot performance regressions before they affect your sales. Celebrate your wins.

Get started with Budgets

Understand the impact of third party code

See the impact of external scripts quickly. Make informed decisions on which tools to use without losing speed.

Analyse the cost of Third Parties

Calibre offers first-class support for web performance monitoring.

Addy Osmani, Engineering Manager

chrome

Review changes in Pull Requests

Spot performance changes before releasing to production. Bring accountability to the entire development team.

Review performance before releases

Automate your performance system

Create tests and access metrics in a breeze. Export data and integrate with your favourite tools.

Start scripting with Node.js API

Receive regular performance reports

Save hours on distilling performance data. Receive beautiful reports on crucial metrics, weekly or monthly.

Get Insights Report in your email

Be confident of results

Never question your performance data. Calibre runs an AI-powered validation engine to ensure the most reliable performance results on the market.

Start your free 15-day trial

Set up in minutes. Nothing to install.