To set a custom search engine as the default in Google Chrome, follow these steps based on the information provided:

For Computers (Windows, macOS, Linux):

  1. Open Google Chrome.
  2. Click the More (three-dots) icon in the upper-right corner.
  3. Select Settings.
  4. Scroll down to the 'Search engine' section or locate it in the left sidebar.
  5. Click the dropdown menu labeled 'Search engine used in the address bar'.
  6. Choose your desired search engine from the list or click 'Manage search engines' to add a non-listed search engine.
    • If adding a new search engine, click 'Add', fill in the details, and select 'Make default' once added.
  7. Close the Settings tab.

For Android Devices:

  1. Open the Google Chrome app.
  2. Tap the More (three-dots) icon in the upper-right corner.
  3. Select Settings.
  4. Tap Search engine.
  5. Choose your desired search engine from the list or tap 'Manage search engines' to add a non-listed search engine.
    • If adding a new search engine, click 'Add', fill in the details, and select 'Set as default' once added.

For iOS Devices (iPhone or iPad):

  1. Open the Google Chrome app.
  2. Tap the More (three-dots) icon in the lower-right corner.
  3. Select Settings.
  4. Tap Search Engine.
  5. Choose your desired search engine from the list; currently, you cannot add a non-listed search engine directly within the iOS version of Chrome.

Remember to close the Settings tab or return to the main interface after making changes for the modifications to take effect.