📡 HAR File Viewer
📂 Upload HAR File
Drop HAR file here, or click to select
Supports .har / .json formats
What Can the HAR File Viewer Do?
The HAR File Viewer is a free online tool that quickly parses and analyzes HAR (HTTP Archive) files exported from browser developer tools. After you drag in a file, you can view detailed information for every HTTP request, including request URL, method, status, response time, request/response headers, and body sizes. All processing runs locally in your browser — your HAR file is never uploaded to any server.
Key Features
- Request List: table view of all HTTP requests, filterable by URL, method, and status
- Timeline: chart showing each request's duration to spot slow requests quickly
- Status Distribution: chart showing the 2xx/3xx/4xx/5xx breakdown
- Domain Stats: chart showing per-domain request counts and total traffic
- Size Ranking: TOP 20 largest response bodies sorted, to help optimize load performance
How to Use
1. Open Chrome DevTools with F12 and switch to the Network tab
2. Refresh the page or perform the operations you want to capture
3. Right-click the request list and choose "Save all as HAR with content" to export
4. Drag the HAR file onto this tool to upload it
5. The file is parsed automatically and you can browse the request list and statistics charts
Use Cases
Case 1: Performance Optimization
Frontend developers use the HAR Viewer to analyze all requests during a page load and identify the slowest interfaces or resources for targeted optimization.
Case 2: API Debugging
Backend developers inspect HAR files to review complete API request information — request headers, request bodies, response status, and response content — to quickly locate issues.
Case 3: Security Audit
Security engineers review HAR files for sensitive information leaks, checking for plaintext tokens, passwords, and other sensitive data.
FAQ
Does a HAR file contain sensitive information?
Yes, HAR files may contain sensitive data such as cookies, tokens, and passwords. Do not share HAR files with untrusted third parties. All processing happens on your device — data is never uploaded.
Is the HAR File Viewer free?
Yes, completely free. The viewer parses HTTP Archive files and visualizes network request timelines, status distributions, and domain stats. It supports drag-and-drop upload, requires no registration, and works entirely in your browser.
Can encrypted HAR files be parsed?
No. HAR files are standard JSON format. If encrypted or compressed, they must be decrypted first.