The HTTP Archive (HAR) format records what network requests are made by the browser when accessing a website.
Click each request to expand it and view additional details.
View the HTTP request and response headers for each network request.
See how the server responded to each browser request.
Get a detailed size analysis for HTML and CSS responses to see what contributes to their download size.
HAR files just show basic info on network requests. But a full page speed test will tell show you key performance metrics and a rendering filmstrip showing when content becomes visible.
See what requests are render-blocking, what resources are preloaded, and how different resources related to each other.
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