60% vs 65% vs 75%
The jump from 60% to 65% adds dedicated arrows and a small navigation column. The jump to 75% adds a function row. Choose the actions you use repeatedly before choosing the smallest body.
On a 60% board, arrow and function actions come from another layer. Find its Fn key and the exact arrow mapping in the board’s instructions; different boards place them differently.
Full size, TKL and compact numpads
A full-size board separates the typing, editing and number-pad groups. TKL retains the editing keys but leaves out the number pad. A 96% or 1800-style arrangement keeps numeric entry in a shorter body by reducing gaps or moving navigation keys.
Check Num Lock, number-pad Enter, 0 width and Delete/Home/End placement when comparing compact number-pad boards. A separate number pad can also be positioned independently of a TKL board.
Why key counts differ
The examples above count the keys you can see. ANSI, ISO and JIS change some positions, and 75%, 65% and 96% boards often have different navigation or modifier keys. The percentage name describes a family rather than one exact key count.