F hook in crochet measures 3.75mm, smaller than the common H hook at 5.0mm, typically used with sport or DK weight yarn for a tighter, denser fabric than worsted weight projects. I reach for an F hook for amigurumi specifically, where a tighter gauge hides stuffing better. This guide gives the direct size.

Direct Answer
The F hook measures 3.75mm, commonly paired with sport to DK weight yarn, well suited to amigurumi and other projects wanting a denser, tighter fabric.

Frequently asked questions
What yarn weight pairs best with an F hook?
Sport to DK weight yarn typically pairs best with an F hook, giving a tighter, denser fabric than the same yarn worked with a larger hook.
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