Get instant page performance insights with Performance-Bookmarklet, trusted by 1.1k+ GitHub stars, ideal for startup founders optimizing website speed.
intermediate⏱ 5 minutes💵 Free
1,150 stars84 forksJavaScriptQuality 8/10Updated 3/3/2023100% free · open source
What it is
Click a bookmarklet to instantly analyze this webpage's speed and performance.
What you can make with it
Use the insights to automate website optimization tasks and boost user experience.
How it helps
This helps you quickly identify and fix performance issues, improving your website's loading speed and overall user experience.
Real use case example
"A startup founder wants to improve their website's loading speed. They click the Performance Bookmarklet on their homepage. The analysis reveals multiple resource loading issues. They use the insights to optimize images and caching, reducing load times by 30% within a week."
If you're new
Beginners should pick this up when looking for a tool to get their feet wet in web performance analysis.
If you're senior
Senior engineers will reach for this when they need a lightweight, free, and reliable performance analysis solution.
Common confusion cleared up
This is not a replacement for a comprehensive web performance test, but rather a quick, in-browser analysis tool to identify performance bottlenecks.
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Pairs with
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Why we list it on WorkflowStacks: The marketplace includes Performance Bookmarklet because it's a free and open-source tool with industry-standard analysis capabilities.
What it does
Performance-Bookmarklet analyzes webpage performance using the Resource Timing API, Navigation Timing API, and User-Timing, providing insights into load times, requests, and more.
Install / run
Drag and drop the Performance-Bookmarklet link from the GitHub repository into your browser bookmarks bar
When to use it
•When you need to quickly identify performance bottlenecks on your website
•When you want to compare the performance of different webpage elements, such as images or scripts
•When you need a lightweight alternative to more comprehensive web performance testing tools
Quick start
1Click the Performance-Bookmarklet bookmark to run the analysis on the current webpage
2Use the 'Sort by' dropdown menu to organize the results by load time, domain, or other criteria
3Explore the 'Requests' tab to view detailed information about the webpage's resource requests
4Use the 'Marks' tab to view custom timing marks set by the webpage
5Refer to the 'About' tab for more information about the Performance-Bookmarklet and its features
Ready-to-paste prompt
https://example.com #?performance-bookmarklet to run the Performance-Bookmarklet analysis on a specific webpage
Heads up: The Performance-Bookmarklet requires a modern browser that supports the Resource Timing API and Navigation Timing API, so ensure your browser is up-to-date before using the tool
Saves to your device
Topics
analyzer
bookmarklet
browser-extension
navigation-timing
performance
performance-metrics
requests
resource-timing
user-timing
waterfall
webperf
What's inside — free to inspect
No purchase needed
Read the entire source before you build — unlike paid marketplaces that hide it behind a buy button.
7
top-level files
2
folders
4.4M
repo size
MIT
license
Key files
package.json
README.md
File tree
dist/
src/
.gitignore
FIREFOX-ADDON-BUILD.md
Gruntfile.js
LICENSE
package-lock.json
package.json
README.md
Quick Actions
Details
Creator
micmro
Language
JavaScript
Category
analytics
Published
10/6/2014
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