I am making an HTML form with multiple inputs. I am using mainly select inputs (as below),

<select>
<option></option>
<option></option>
</select>

and also some radio buttons. I each input represents a different category. I have one category with 20+ possible options. I need an HTML form to do this without taking up a lot of space. Radio buttons wouldn't work, and a select input with 20+ possible options seems a bit over-the-top. Any ideas on what type of input I should use? Or, is it possible to limit the length of the drop-down box, and have a scroll bar on the side?

As you asked:

Any ideas on what type of input I should use?

You could just use the size attribute of select:

<select size='5'>
  <option>example</option>
  <option>example</option>
  <option>example</option>
  <option>example</option>
  <option>example</option>
  <option>example</option>
  <option>example</option>
  <option>example</option>
</select>

However as you can see with this there is no longer a dropdown - but the options are still there, with a controllable limit and a scrollbar.

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