A HAR (HTTP Archive) file captures a complete record of all network activity between your browser and the server during a session. Vercel Support may request a HAR file from you to investigate an issue and identify a root cause.
This guide walks you through generating a HAR file on macOS and Windows across all major browsers.
Sensitive data warning: HAR files can contain cookies, session tokens, authorization headers, and request payloads. Only share HAR files with Vercel Support directly as an attachment to your support case, and avoid sharing them publicly.
- While a HAR file is being recorded, keep the recording running while you trigger the exact behaviour you're reporting. Don't stop recording until after the issue occurs.
- We recommend recording HAR files in a private/incognito browsing window. This prevents cached data and extensions from interfering with the capture.
Once you have your .har file:
- Attach it directly to your Vercel Support support case.
- Include a brief description of:
- The URL(s) where the issue occurred
- The exact steps you took to reproduce it
- The timestamp (approximately) when the issue appears in the recording
1. Open Chrome and navigate to the page where the issue occurs.
2. Open DevTools using one of these methods:
- Keyboard:
Cmd + Option + I - Right-click anywhere on the page → Inspect
3. Click the Network tab in the DevTools panel.
4. Check the Preserve log checkbox to retain entries across page navigations.
5. Check Disable cache to ensure all requests are captured fresh.
6. Clear any existing logs by clicking the 🚫 in the top-left of the Network pabel.
7. Ensure the record button (●) in the top-left of the Network panel is active (red). If it's grey, click it to start recording.
8. Reproduce the issue — reload the page or trigger the action that causes the problem.
9. After reproducing the issue, select the download button (downward arrow icon).
10. Save the file to your Desktop or another convenient location to share with Vercel Support.
1. Open Firefox and navigate to the affected page.
2. Open DevTools:
- Keyboard:
Cmd + Option + I - Menu: Tools → Browser Tools → Web Developer Tools
3. Select the Network tab.
4. Click the gear icon (⚙) in the top-right of the Network panel.
5. Select Persist Logs to retain requests across reloads.
6. Check the Disable Cache checkbox at the top-right of the Network panel to ensure all requests are captured fresh.
7. Reproduce the issue — reload the page or trigger the action that causes the problem.
8. Click the gear icon (⚙) in the top-right of the Network panel, or right-click any request.
9. Select Save All As HAR.
10. Save the file to your Desktop or another convenient location to share with Vercel Support.
Important: Safari requires you to enable the Develop menu before accessing network tools.
Enable the Develop menu (one-time setup):
1. Open Safari → Settings (or Preferences on older macOS).
2. Click the Advanced tab.
3. Check Show features for web developers (or "Show Develop menu in menu bar" on older versions).
Capture the HAR file:
1. Open the affected page in Safari.
2. From the menu bar, go to Develop → Show Web Inspector, or press Cmd + Option + I.
3. Click the Network tab.
4. Check Disables Caches in the top-right of the Network panel to ensure all requests are captured fresh.
5. Reproduce the issue — reload the page or trigger the action that causes the problem.
6. Click the Export button (downward arrow icon) in the top-right corner of the Network panel.
7. Save the file to your Desktop or another convenient location to share with Vercel Support.
1. Open Chrome and navigate to the affected page.
2. Open DevTools:
- Keyboard:
F12orCtrl + Shift + I - Right-click anywhere on the page → Inspect
3. Click the Network tab.
4. Check Preserve log to retain entries across page navigations.
5. Check Disable cache to ensure all requests are captured fresh.
6. Reproduce the issue — reload the page or trigger the action that causes the problem.
7. After reproducing the issue, select the download button (downward arrow icon).
8. Save the file to your Desktop or another convenient location to share with Vercel Support.
1. Open Firefox and navigate to the affected page.
2. Open DevTools:
- Keyboard:
F12orCtrl + Shift + I - Menu: ☰ → More Tools → Web Developer Tools
3. Select the Network tab.
4. Click the gear icon (⚙) in the top-right of the Network panel.
5. Select Persist Logs to retain requests across reloads.
6. Check the Disable Cache checkbox at the top-right of the Network panel to ensure all requests are captured fresh.
7. Reproduce the issue — reload the page or trigger the action that causes the problem.
8. Click the gear icon (⚙) in the top-right of the Network panel, or right-click any request.
9. Select Save All As HAR.
10. Save the file to your Desktop or another convenient location to share with Vercel Support.
1. Open Edge and navigate to the affected page.
2. Open DevTools:
- Keyboard:
F12orCtrl + Shift + I - Menu: ··· → More tools → Developer tools
3. Click the Network tab.
4. Check the Preserve log checkbox to retain entries across page navigations.
5. Check Disable cache to ensure all requests are captured fresh.
6. Clear any existing logs by clicking the 🚫 in the top-left of the Network panel.
7. Ensure the record button (●) in the top-left of the Network panel is active (red). If it's grey, click it to start recording.
8. Reproduce the issue — reload the page or trigger the action that causes the problem.
9. After reproducing the issue, select the download button (downward arrow icon).
10. Save the file to your Desktop or another convenient location to share with Vercel Support.
