Heatmap of resources loaded in the browser using the Resource Timing API

Perfmap promo image
What is Perfmap?

Perfmap is a Chrome extension by This extension has 5,557 weekly active users, a good user rating of 4.69, and was removed from Chrome Web Store 2 years ago. The latest version, 1.2, was updated 8 years ago.

This extension was removed from Chrome Web Store on 2021-04-06
Stats date:
Users: 5,557
Rating: 4.69 (13)
Version: 1.2 (Last updated: 2014-10-25)
Manifest version: 2
  • tabs
  • http://*/*
  • https://*/*
Size: 148.48K
Price: Free
Risk impact: High risk impact
Risk likelihood: High risk likelihood
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Other platforms

Not available on Firefox
Not available on Edge
A front-end performance heatmap of resources loaded in the browser using the Resource Timing API.

The heatmap colours and the first ms value indicate at what point in the page load did the image finished loading. It's a good indicator of user experience. "It took 3450ms before the user saw this image." The second value in brackets is the time it took the browser to load that specific image.

The legend attached to the bottom of the page shows timings for the full page load and hovering over a coloured area on the heatmap will move the timeline indicator to show you when that image was fully loaded.

Risk impact

Perfmap requires a number of risky permissions that can potentially harm your browser and steal your data. Exercise caution when installing this extension. Review carefully before installing. We recommend that you only install Perfmap if you trust the publisher.

Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypass your security settings, and access your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

Risk likelihood

Perfmap may not be trust-worthy. Avoid installing if possible unless you really trust this publisher.

Risk likelihood measures the probability that a Chrome extension may turn malicious. This is determined by the publisher and the Chrome extension reputation on Chrome Web Store, the amount of time the Chrome extension has been around, and other signals about the Chrome extension. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Chrome extension, especially ones with higher risk impact and/or higher risk likelihood.

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User reviews
+Me sorprendió la manera de mostrar las estadísticas. -Se podrían poner más claros los tiempo.
by Jo Be, 2017-10-18

Could you please that I am able to modify the text result. Like change the font size maybe? Thank you

Great tool. Really useful. Thanks a lot.
by Laur Rent Laur Rent, 2015-08-08
View all user reviews
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