How do I start the timer?

Hold the spacebar for about half a second. The display switches to "Inspect" and begins a 15-second countdown. Release Space to start the solve timer, then press Space again to stop it when you finish.

What are Ao5 and Ao12?

Ao5 is the average of your last 5 solves with the best and worst times removed. Ao12 is the same but over your last 12 solves. These are the standard WCA competition metrics for measuring speedcubing consistency.

Is inspection required?

This timer starts its inspection workflow after you hold Space for about 0.4 seconds; releasing earlier cancels the start. Once inspection begins, release Space whenever you are ready to start the solve.

Does the timer save my session?

Solves are stored in your browser's localStorage and persist across page reloads. Click "Clear Session" to reset all times.

What happens if inspection time runs out?

After 15 seconds, the inspection bar turns red and a +2 penalty notice appears below the controls. The timer still starts normally when you release Space — the penalty is a reminder only and is not added automatically.

Rubik's Cube Timer

Speedcubing timer with spacebar start/stop, 15-second inspection countdown, session history, and Ao5/Ao12 averages.

Hold Space to begin inspection

0.000

Solves

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Best

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Mean

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Ao5

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Ao12

Session History

0 solves

No solves yet. Complete a solve to start tracking.

Summary

A client-side speedcubing timer with a streamlined inspection workflow: hold Space to begin the 15-second countdown, release to start the solve, and press Space again to stop. Each solve is logged with a timestamp, and the session panel shows your best time, mean, Ao5, and Ao12 averages updated after every solve. All data stays in your browser.

How it works

Hold the spacebar (or tap and hold the Start button on mobile) to begin the 15-second inspection countdown.
Release Space when you are ready — the solve timer starts immediately.
Press Space again (or tap Stop) to stop the timer when you finish the solve.
The time is logged to your session history automatically.
Your best time, mean, Ao5, and Ao12 update after each solve.
Delete any individual solve by clicking the trash icon next to it.

Use cases

Track your solving progress across a practice session.
Monitor Ao5 and Ao12 trends to measure consistency.
Simulate WCA inspection rules with the 15-second countdown.
Compare your personal best across multiple sessions.
Use on a phone or tablet during casual cube practice.
Identify outlier solves that pull your average up.

Frequently Asked Questions

Last updated: 2026-06-11 · Reviewed by Nham Vu