Cube Timer

The Cube Timer is a free online speedcubing timer built to match how solves are timed at official World Cube Association (WCA) competitions. Hold the spacebar to get ready, release to start, and press any key to stop — so your reaction time never inflates your result. Every solve is measured to the hundredth of a second and rolled into the averages cubers actually track: ao5, ao12, best single, mean of 3, and your best rolling averages of the session. A built-in scramble generator covers everything from the 2×2 to the Megaminx, and the 2×2 to 5×5 show a colored net so you can double-check you scrambled correctly.

How to Use the Cube Timer

1. Pick your puzzle from the tabs (2×2 through Megaminx). A fresh scramble appears automatically, with a colored preview for the 2×2 to 5×5.
2. Scramble your cube by following the notation and check it against the preview. Toggle 15s inspection on if you want to practice competition-style.
3. Hold Space (or touch and hold the timer on a phone) until it glows green, then release to start solving.
4. Press any key or tap to stop. Your ao5, ao12, ao100 and best single update instantly, the progress chart grows, and a new scramble is queued.
5. Review your session: tag solves +2 or DNF in the history, use Copy times to share it, or download it as a CSV file.

What Makes This Cube Timer Different

• True WCA spacebar timing — a hold-to-arm delay (adjustable, or instant) means the clock starts the instant you lift your hands, exactly like a competition Stackmat.
• Real inspection mode — an optional 15-second countdown with a color ring and audible cues at 8 and 12 seconds, plus automatic +2 and DNF penalties for overrunning, just as the regulations require.
• Scramble preview for 2×2 to 5×5 — the scramble is applied to a virtual cube and drawn as a colored net, so you can confirm your physical cube matches before you start.
• Progress you can see — ao5, ao12, ao50 and ao100, your best averages, and a chart of your last 100 solves with the rolling ao5.
• Seven puzzles — 2×2, 3×3, 4×4, 5×5, Pyraminx, Skewb, and Megaminx, each with its own scramble format and its own saved session.
• Offline and private — all times live in your browser's local storage. No sign-up, no upload, works on a plane.

How Spacebar Timing Works

Speedcubers do not press "start" and then reach for the cube — that would count reaction time as solve time. Instead you rest your hands on the timer, hold, and the moment your hands leave, the clock begins:

1. Hold the spacebar (or touch and hold the timer on mobile). The display turns red.
2. Once you have held long enough to be armed, it turns green — you are ready.
3. Release to start the clock and solve.
4. Press any key or tap the screen to stop. Your time drops straight into the history.

Understanding WCA Averages

A speedcuber's headline number is almost never a single solve — it is an average, because averages reward consistency. The two most important are the average of 5 and the average of 12:

An average of 5 (ao5) takes your last five solves, throws out the fastest and the slowest, and averages the remaining three. An average of 12 (ao12) does the same over twelve solves, dropping the best and worst and averaging the middle ten. Formally, for a window of \( n \) solves the timer trims \( \lceil 0.05n \rceil \) results from each end:

$$\text{ao}n = \frac{1}{\,n - 2k\,}\sum_{i=k+1}^{\,n-k} x_{(i)}$$

$$k = \lceil 0.05\,n \rceil$$

where \( x_{(i)} \) are the solve times sorted from fastest to slowest. A DNF counts as the worst possible result: with one DNF in the window it is simply the value the trim discards, but with two or more DNFs the whole average becomes a DNF.

Penalties: +2 and DNF

Tap any solve in the history to tag it +2 or DNF, or to delete it — handy when you catch a pop or a misalignment after the fact.

Scramble Notation Quick Reference

Scrambles use standard Singmaster notation. A letter is a quarter turn of that face clockwise; a following apostrophe means counter-clockwise, and a 2 means a half turn:

• U / D — Up / Down face  ·  L / R — Left / Right face  ·  F / B — Front / Back face
• ' (apostrophe) — turn that face counter-clockwise, e.g. R'
• 2 — turn that face 180°, e.g. U2
• w (on 4×4 and 5×5) — a wide turn that moves the outer two layers together, e.g. Rw

Keyboard Shortcuts

Frequently Asked Questions