How to Add Cookie in Selenium: Syntax and Example

To add a cookie in Selenium, use the add_cookie() method on the WebDriver instance with a dictionary containing cookie details like name and value. Make sure to add cookies only after navigating to a domain, as cookies are domain-specific.

Syntax

The add_cookie() method requires a dictionary with at least name and value keys. Optional keys include path, domain, secure, and expiry.

• name: The cookie's name (string).
• value: The cookie's value (string).
• path: The path for the cookie (string, optional).
• domain: The domain for the cookie (string, optional).
• secure: Whether the cookie is secure (boolean, optional).
• expiry: Expiration time as UNIX timestamp (int, optional).

Cookies must be added after navigating to a page on the target domain.

python

driver.add_cookie({'name': 'cookie_name', 'value': 'cookie_value'})

Example

This example shows how to open a website, add a cookie, and verify it was added successfully.

python

from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from selenium.webdriver.chrome.options import Options

options = Options()
options.add_argument('--headless')
service = Service()
driver = webdriver.Chrome(service=service, options=options)

try:
    driver.get('https://www.example.com')
    cookie = {'name': 'test_cookie', 'value': '12345'}
    driver.add_cookie(cookie)
    retrieved_cookie = driver.get_cookie('test_cookie')
    assert retrieved_cookie is not None
    assert retrieved_cookie['value'] == '12345'
    print('Cookie added and verified successfully.')
finally:
    driver.quit()

Output

Cookie added and verified successfully.

Common Pitfalls

• Trying to add a cookie before navigating to any page causes an error because Selenium needs a domain context.
• Not including required keys like name or value in the cookie dictionary will raise exceptions.
• Adding cookies with incorrect domain or path may cause them to be ignored.

Always navigate to the target domain first, then add cookies.

python

from selenium import webdriver

driver = webdriver.Chrome()

# Wrong: Adding cookie before loading a page
try:
    driver.add_cookie({'name': 'wrong', 'value': 'fail'})
except Exception as e:
    print(f'Error: {e}')

# Right: Navigate first, then add cookie

driver.get('https://www.example.com')
driver.add_cookie({'name': 'right', 'value': 'success'})
print('Cookie added after navigation')
driver.quit()

Output

Error: You must navigate to a page before adding cookies
Cookie added after navigation

Quick Reference

• Use driver.get() to open the domain before adding cookies.
• Cookies must have name and value.
• Use driver.get_cookie(name) to verify a cookie.
• Use driver.delete_cookie(name) to remove a cookie.

Key Takeaways

Always navigate to the target website before adding cookies in Selenium.

Use a dictionary with at least 'name' and 'value' keys to add a cookie.

Verify cookies with get_cookie() after adding them.

Avoid adding cookies before page load to prevent errors.

Set optional cookie attributes like 'path' and 'expiry' as needed.