Page Speed Bottleneck Finder

Find the requests that hold up rendering

See how different resources impact pages speed

Identify what requests you need to optimize to make your website load faster.

Check impact on FCP, LCP, and H1 timing

There's no single load time for a web page. We look at different page load milestones and show how each request impacts them.

Spot hidden bottlenecks beyond render-blocking CSS

Async scripts that fetch data before showing content, SPA data requests, and bundle chunks can all delay rendering even when they don't look render-blocking.

How does the website bottleneck finder work?

1. We measure a baseline

First we open your page and measure how long it takes for your content to render. We also collect a list of network resources that could potentially slow down your site.

2. We delay one request at a time

Then we load the page again and again, holding back one request at a time, and measuring how slower your page loads.

3. We rank requests by impact

If delaying a request pushes rendering back, that request is on the critical path. You can then focus optimizations here.

Run a full page speed analysis

Get performance recommendations

While our bottleneck finder identifies what requests slow down your website, our full page speed test analyzes your website more holistically and provides actionable tips on how to improve it.

See real user data from Google

Monitor web performance continuously

A one-off test only tells you about today

Optimizing a bottleneck is only worth it if it stays fixed. DebugBear runs scheduled tests and alerts you in Slack, Microsoft Teams, or by email when your metrics regress.

Find out what changed

Compare test results from before and after a regression to see exactly which requests, scripts, or page elements are responsible.

Lab data and real user data together