Features take one thing

Find what font a website is actually using

F Fonts in use in the toolbar, free with no account

The question is never "what does the stylesheet ask for", it is "what am I looking at". A stack that wants Inter and is quietly getting Helvetica renders as Helvetica, and this says so.

What you get

The family actually rendering: Established by measuring the text against fallbacks, not by trusting the first name in the font-family list.
Hover to identify: A chip follows the cursor with the family, size and weight of whatever text is under it.
Every family on the page: Each size with the weights it appears in and how often, webfonts flagged and their files named.
Declared but unavailable: Families the page asks for and does not get are called out, which is the whole reason the page looks wrong to you and right to them.
The licence question, raised: Font files are licensed. The panel says so before you ship one.

How to use it

Press Alt+Shift+P, then F.
Hover any text to identify it. Click to copy the whole stack.
Read the panel for every family on the page at once.

What it will not do

Text drawn into a canvas or baked into an image is a picture of text, and no font detector can read it.
Availability is measured, so a family that renders identically to a fallback at that size cannot be told apart from it.

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Find what font a website is actually using

What you get

How to use it

What it will not do

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