How to use the Network tab in DevTools? How to determine why the page loads slowly?

The Network tab in DevTools allows you to track all network requests made by the page: loading HTML, CSS, JS, images, API requests, etc.

To determine why the page loads slowly, you should:

• Look at the load time of each resource (the Time column).
• Pay attention to the request statuses — check for errors or long waits.
• Check which resources take the longest to load (e.g., large images or heavy scripts).
• Use filters to highlight resource types (JS, CSS, XHR).
• Observe the loading sequence — there might be blocking scripts or resources.

For example, if the main HTML loads quickly but images load slowly afterward, you can optimize their size or use lazy loading. If API requests respond slowly, the issue might be on the server or network.