Use this unknown Google API to fetch the favicon image for any domain/subdomain with the ability to specify a custom size as well!

https://www.google.com/s2/favicons?domain=<domain_name>&sz=<size>

Do not forget or remove the www part, the API doesn't work without it.

1. Replace the <domain_name> with the domain/subdomain URL you wish to get the Favicon for.
2. Replace the <size with a number in pixels you would like the image to be returned in.

By default the Favicon image returned is 16x16 pixels, the same applies if the specified size is not found or incorrect.

The API redirects you to a cached URL and response which make using it very fast as it is backed by Google's own world-leading CDN infrastructure.

For Example:

https://www.google.com/s2/favicons?domain=jsdelivr.com&sz=64

Redirects you to the URL https://t1.gstatic.com/faviconV2?client=SOCIAL&type=FAVICON&fallback_opts=TYPE,SIZE,URL&url=http://jsdelivr.com&size=64 which displays the following Favicon image

If a favicon for the domain is not found, it returns a weird image probably not suitable to be displayed or used anywhere so someway of finding a fallback path would be nice.

Favicon Not Found image: