What is a HAR file?
A HAR file (HTTP Archive) is a log file that records all communication between your browser and a website.
It captures detailed technical data, including:
Network requests and responses
Loading times for each resource
Error messages and status codes
Cookies and headers
In simple terms, a HAR file provides a complete “behind-the-scenes” view of what happens when a webpage loads, making it an essential tool for troubleshooting.
When should I create a HAR file?
You may be asked to generate a HAR file if:
A page loads slowly
A feature is not working as expected
You encounter error messages
The system becomes unresponsive
The file helps support teams identify exactly where and why an issue occurs.
How to download a HAR file
Google Chrome and Microsoft Edge
Open the page where the issue occurs
Press F12 (or right-click → Inspect)
Go to the Network tab
Make sure recording is active (red ● icon)
Refresh the page
Reproduce the issue
Click the download icon (Export HAR)
Alternatively: right-click inside the network list → “Save all as HAR”
Mozilla Firefox
Press F12
Go to the Network tab
Refresh the page
Reproduce the issue
Right-click inside the list
Select “Save All As HAR”
Safari (Mac)
Enable Developer tools (Settings → Advanced → Show Develop menu)
Open Develop → Show Web Inspector
Go to the Network tab
Refresh the page and reproduce the issue
Click Export HAR
Best practices
To ensure the HAR file is useful:
Start recording before reproducing the issue
Refresh the page after opening the Network tab
Close other browser tabs to reduce noise
Use a private/incognito window for cleaner data
⚠️ Important: Sensitive data
A HAR file may contain sensitive information such as:
Cookies
Session data
Authentication tokens
Only share HAR files with trusted parties, such as Addo Support.
Need help?
If you are unsure how to create a HAR file, feel free to contact Addo Support—we are happy to guide you step by step.