GUIDE 06
Keyboard Tapping — Switches, Two-Key Alternating and Rollover
How switch type affects keyboard tapping speed, tips for alternating between two keys, and how key repeat and rollover work.
Spacebar spamming and two-key streams in rhythm games may look similar to mouse clicking, but the hardware works differently. Here's what you need to know to make sense of your keyboard tapping scores.
Switch types and actuation point
- Membrane: Pressing a rubber dome closes the circuit. In many cases the key has to go all the way down to register.
- Mechanical: Metal-contact switches that register partway down, before bottoming out. Pressing only to the actuation point and releasing shortens the travel.
- Optical and magnetic (Hall effect): Detect presses with light or a magnetic field. Some magnetic keyboards let you adjust the actuation point or treat the key as released as soon as it starts coming back up, which can be an advantage for tapping.
Alternating between two keys
Alternating between two keys with two fingers halves the load on each finger compared with tapping one key with one finger. It's the standard approach in rhythm games like osu!.
- Use two neighboring fingers, such as your index and middle fingers.
- Rest your wrist on the desk and move only your fingers.
- Work on your alternation rate before speed. Once you stop accidentally hitting the same key twice in a row, speed follows.
CPS Meter's keyboard tapping test shows presses per key and the “alternation rate” in two-key mode. The closer to 100%, the cleaner your alternation.
Key repeat (auto-repeat)
If you hold a key down, after a short delay the operating system starts generating the same input repeatedly. That's handy for typing but counts as cheating in a tapping test. This tool ignores repeat inputs and only counts a press once you release the key and press it again.
Rollover and ghosting
When you press several keys at once and some inputs get lost, that's called ghosting; the number of keys that can be recognized simultaneously is called rollover. Alternating between two keys is fine on most keyboards, but budget keyboards can drop inputs on certain key combinations. If one key's press count looks suspiciously low in your results, try a different key pair.
Spacebar tapping
The spacebar is a long key with stabilizers supporting both ends, and pressing near the edges can feel scratchy. Pressing in the middle gives more consistent input. In CPS Meter's CPS test, set the input to “Spacebar” to measure spacebar tapping instead of mouse clicks.
Practice tips
- Build your rhythm in short modes (5–10 seconds) first, then check your endurance at 30 seconds.
- If your interval standard deviation jumps as you push for speed, you're overdoing it.
- Rest if your fingers or wrist feel stiff. Stretches are covered in the “Wrist Health” guide.