How to Pass Cookies to aria2?

This article provides a practical guide on how to pass authentication cookies to the aria2 command-line download utility. When downloading files from websites that require a login, providing session cookies is essential to prevent “403 Forbidden” or “401 Unauthorized” errors. Below, you will find the specific command-line flags required, methods for exporting cookies from your web browser, and examples of how to format your download commands.

Using the --header Flag

The most direct way to pass a cookie to aria2 is by injecting it into the HTTP request header using the --header option. This is ideal for quick, one-off downloads where you already have the specific cookie string copied.

The syntax requires you to pass the Cookie: attribute followed by the key-value pairs of your session tokens.

aria2c --header="Cookie: session_id=xyz123; user_token=abc456" "https://example.com/protected-file.zip"

Using the --load-cookies Flag

For websites with complex authentication or multiple tracking cookies, exporting a cookie file from your browser is the most efficient approach. aria2 can natively read cookie files formatted in the standard Mozilla/Netscape format.

Step 1: Export Cookies from Your Browser

You can use browser extensions to export your active session cookies into a text file (usually named cookies.txt).

Step 2: Run the aria2 Command

Once you have saved the file, use the --load-cookies flag to point aria2 to the path of your exported file.

aria2c --load-cookies=cookies.txt "https://example.com/protected-file.zip"

Handling Cookies in Input Files

If you are batch-downloading multiple links using an input text file (-i or --input-file), you can define cookies globally for all links in that session, or specify them per URL within the input file itself.

Global Cookies for Input Files

To apply the same cookie file to every URL listed inside links.txt:

aria2c --load-cookies=cookies.txt -i links.txt

Inline Cookies per URL

If the URLs in your text file come from different websites requiring different authentication, you can format your input file to specify options on the lines directly beneath the target URL:

https://site1.com/file1.zip
  header=Cookie: session=site1_token_here
https://site2.com/file2.zip
  header=Cookie: session=site2_token_here

Important Considerations