HAR File Viewer
View and analyze HTTP Archive (HAR) files with detailed request/response data
Last updated: November 13, 2025
How to use
- Export HAR file from browser DevTools (Network tab → right-click → Save all as HAR)
- Upload the HAR file using the file input above
- Browse the list of network requests
- Click on any request to view detailed information
- Use the filter to search for specific URLs or HTTP methods
About HAR Files
HAR (HTTP Archive) is a JSON-formatted archive file format for logging web browser's interaction with websites. It contains detailed performance data about web pages, including requests, responses, headers, cookies, and timing information.
Result actions
Copy or download the tool output, or share a link to HAR File Viewer.
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What is a HAR File Viewer?
A HAR (HTTP Archive) file viewer displays and analyzes HTTP Archive files exported from browser DevTools. HAR files contain detailed information about network requests including URLs, headers, responses, timings, and performance data. Viewing HAR files helps debug web applications, analyze network traffic, and optimize page performance.
Why View HAR Files?
HAR file viewing is essential for web development:
- Network Debugging: Debug network requests and API calls
- Performance Analysis: Analyze page load times and resource loading
- Request Inspection: Inspect HTTP headers, responses, and status codes
- Traffic Analysis: Understand network traffic patterns
- Optimization: Identify performance bottlenecks and optimization opportunities
Common Use Cases
Network Request Analysis
Analyze network requests from browser DevTools. View all HTTP requests made by web pages to understand network behavior.
API Debugging
Debug web application API calls. Inspect API requests, responses, headers, and status codes to identify issues.
Performance Optimization
Review network timings and performance data. Identify slow requests, large responses, and optimization opportunities.
Header Inspection
Inspect HTTP headers and responses. Understand request/response headers, cookies, and authentication data.
Web Page Auditing
Audit web page resource loading. Understand which resources are loaded, their sizes, and load times.
HAR File Format
HAR files contain:
- Requests: All HTTP requests made by the page
- Responses: Response data, headers, and status codes
- Timings: Request timing information (DNS, connect, send, wait, receive)
- Headers: Request and response headers
- Cookies: Cookie information
- Content: Response content and sizes
HAR File Viewing Features
Our viewer provides:
- File Upload: Upload HAR files from browser DevTools
- Request List: View all network requests in organized list
- Detailed View: Inspect individual request details
- Header Display: View request and response headers
- Timing Information: Display performance timings
- Search and Filter: Find specific requests quickly
HAR File Best Practices
- Export from DevTools: Export HAR files from browser DevTools
- Privacy: Be cautious with HAR files containing sensitive data
- File Size: Large HAR files may take time to load
- Analysis: Use HAR files for debugging and optimization
- Sharing: Share HAR files carefully (may contain sensitive data)
Privacy and Security
⚠️ Important: HAR files may contain sensitive data including authentication tokens, cookies, and request/response content. Our HAR File Viewer processes files entirely in your browser, but be cautious when sharing HAR files as they may contain sensitive information.
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