Improving your page speed often requires support from various tools. Some of these tools are used to measure page speed, while others are used to reduce the size of your page assets. In this article, we've created a library to serve as a handy reference.

If we need to list the areas covered by the tools in this article:

  • Tools to determine page speed
  • Tools to reduce image size
  • CSS, JavaScript, HTML optimization tools

Tools to Determine Page Speed

  1. Google Pagespeed Insights:  The most well-known page speed tool. It scores sites using the Lighthouse infrastructure and provides data from the past 28 days.
  2. Webpagetest: A platform that performs three different tests on its infrastructure to provide average results and offers a more technical report with an API.
  3. The only platform that presents visual data for the last 12 months based on Pagespeed and CrUX infrastructure.
  4. GTmetrix: A tool that provides insights on site speed using the Lighthouse infrastructure and gives its own score.
  5. Dareboost: A tool that provides site speed information on its infrastructure.
  6. Calibri App: A tool that allows you to compare multiple pages with competitors using the Lighthouse infrastructure.
  7. SpeedCurve: A paid tool where you can find RUM and synthetic site speed data.
  8. Yellowlab: A useful tool that provides unique improvable metrics on its infrastructure.
  9. Speed Kit: One of the rare tools that not only diagnoses but also treats site issues, available as a WordPress plugin and for normal sites.
  10. A lightweight performance plugin for WordPress.

Tools to Reduce Image Size

  1. A tool for reducing image sizes, with an API and a WordPress plugin.
  2. A very simple and fast tool for converting images to formats like MozJPEG, OptiPNG, and WebP.
  3. TinyJPG: A simple tool for reducing JPG sizes.
  4. TinyPNG: The PNG version of the previous tool.
  5. A platform that compresses JPEG, PNG, GIF, and SVG formats and stands out with its comparative visuals.
  6. Kraken: One of the oldest and most robust tools with API support, offering JPEG, PNG, GIF, Animated GIF, and SVG formats, along with WordPress and Magento plugins.
  7. Optimizilla: A simple and highly useful JPEG and PNG file compressor.
  8. ImageOptim: An online tool, particularly useful for batch image compression on Mac computers.
  9. Crush Pics: A tool offering lossless optimization for images with Shopify and WordPress plugins, also available via API.
  10. Minifier: An SEO-friendly tool for Shopify that generates alt tags for images.
  11. GIMP Save for Web: An application for Windows that allows batch image compression.
  12. Website Image Analysis Tool: A tool that tells you which image format is more optimized based on the input URL.

CSS, JavaScript, HTML Optimization Tools

  1. Refresh-SF: A tool that compresses CSS, JS, and HTML all on one site.
  2. CleanCSS: A widely used tool for CSS compression.
  3. Styleneat: A tool that compresses CSS, JS, and HTML formats on a single platform.
  4. Css Optimizer: A platform that provides CSS optimization.
  5. Tabifier: A platform that compresses HTML, CSS, and JSON code structures.
  6. Minifier: A platform that compresses CSS and JS structures.
  7. Critical CSS: A GitHub source code developed by Addy Osmani to extract critical CSS from pages.
  8. PurifyCSS: A very useful tool that separates unused CSS on a page.

These tools can significantly enhance your website's performance by optimizing various aspects, from page speed measurement to asset size reduction and code optimization.