How to Extract cURL Commands from Chrome Browser

Introduction

Chrome's Developer Tools provide a powerful way to analyze network requests and extract them as cURL commands. This feature is invaluable for developers who need to debug API calls, create documentation, or convert browser requests into code for their applications.

In this guide, we'll walk through the process of extracting cURL commands from Chrome browser, discuss common issues you might encounter, and provide advanced tips for working with the extracted commands.

Why Extract cURL Commands?

Extracting cURL commands from your browser offers several benefits:

Debugging: Reproduce and troubleshoot API requests outside the browser environment
Documentation: Create clear examples for API documentation
Code Generation: Convert browser requests to code in your preferred programming language
Automation: Use the commands in scripts or CI/CD pipelines
Testing: Create test cases for your API endpoints

Step-by-Step Guide to Extract cURL from Chrome

1. Open Chrome Developer Tools

First, open the Chrome Developer Tools by right-clicking anywhere on the webpage and selecting "Inspect" or using the keyboard shortcut:

Windows/Linux: Ctrl + Shift + I or F12
macOS: Cmd + Option + I

2. Navigate to the Network Tab

Click on the "Network" tab in the Developer Tools panel. This tab displays all network requests made by the page.

Tip: If you don't see any requests, try refreshing the page with the Developer Tools open.

3. Perform the Action That Triggers the Request

Interact with the webpage to trigger the network request you're interested in. This could be clicking a button, submitting a form, or any other action that sends data to a server.

4. Find and Select the Request

In the Network tab, locate the request you want to extract. Requests are listed chronologically, but you can filter them by type (XHR, JS, CSS, etc.) using the filter options at the top of the panel.

5. Copy as cURL

Right-click on the selected request and choose "Copy" > "Copy as cURL" from the context menu.

The copied cURL command will look something like this:

curl 'https://api.example.com/data' \
  -H 'authority: api.example.com' \
  -H 'accept: application/json' \
  -H 'content-type: application/json' \
  -H 'user-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64)' \
  -H 'origin: https://example.com' \
  -H 'referer: https://example.com/' \
  --compressed

6. Use the cURL Command

Now you can paste this cURL command into a terminal to execute it directly, or use our Curl to JSON Tool to convert it to code in your preferred programming language.

Common Issues and Solutions

Issue: Missing Authentication Tokens

If your request requires authentication (like cookies or authorization headers), make sure you're logged in when you capture the request.

Warning: Be careful with authentication tokens in your cURL commands. Never share commands containing sensitive tokens publicly.

Issue: Request Not Showing in Network Tab

Sometimes requests might not appear in the Network tab due to various reasons.

Solutions:

Make sure "Preserve log" is checked in the Network tab to keep requests after navigation
Check if the request might be filtered out by the current filter settings
Try disabling browser extensions that might interfere with network monitoring

Issue: cURL Command Too Complex

Chrome includes all headers in the cURL command, which can make it very long and complex.

Solution:

You can simplify the command by removing unnecessary headers. Common headers that can often be safely removed include:

accept-encoding
accept-language
sec-fetch-* headers
cache-control

Advanced Tips

Filtering Requests

Use the filter box in the Network tab to quickly find specific requests:

Filter by domain: type the domain name
Filter by file type: type "css", "js", "img", "xhr", etc.
Filter by status code: type "status:200" or "status:404"
Filter by method: type "method:POST" or "method:GET"

Using Network Request Blocking

Chrome allows you to block specific requests, which can be useful when testing how your application behaves without certain resources:

Right-click on any request in the Network tab
Select "Block request URL" or "Block request domain"
The request will be added to the "Request blocking" tab

Saving and Loading Network Logs

You can save network activity for later analysis:

Right-click anywhere in the Network tab
Select "Save all as HAR with content"
To load a saved HAR file, right-click and select "Import HAR file"

Frequently Asked Questions

Can I extract cURL commands from HTTPS pages?

Yes, Chrome can extract cURL commands from HTTPS pages just as easily as HTTP pages. However, if you're dealing with certificate pinning or custom certificate authorities, you might need to add additional parameters to the cURL command.

How do I handle cookies in the extracted cURL command?

Chrome automatically includes cookies in the extracted cURL command using the -H 'cookie: ...' parameter. If you want to use a cookies file instead, you can modify the command to use --cookie-jar and --cookie options.

Can I extract cURL commands for WebSocket connections?

Chrome's "Copy as cURL" feature doesn't work well with WebSocket connections since WebSockets operate differently from standard HTTP requests. For WebSockets, you might need to use specialized tools or manually construct the connection.

How do I convert the cURL command to code?

You can use our Curl to JSON Tool to convert the extracted cURL command to code in various programming languages including Python, JavaScript, PHP, Java, C#, and more.