HTML for Zip Codes
It seems like zip codes are just numbers, right? So...
<input id="zip" name="zip" type="number">
The advantage there being able to take advantage of free validation from the browser, and triggering a more helpful number-based keyboard on mobile devices.
But Zach pointed out that type="number" is problematic for zip codes because zip codes can have leading zeros (e.g. a Boston zip code might be 02119). Filament group also has a little lib for fixing this.
This is the perfect job for inputmode:
<input id="zip" name="zip" type="text" inputmode="numeric" pattern="^(?(^00000(|-0000))|(d{5}(|-d{4})))$">
But the support is pretty bad at the time of this writing.
A couple of people mentioned trying to hijack type="tel" for it, but that has its own downsides, like rejecting...