What is Ao5? Ao5 is short for "average of 5": you drop your fastest and slowest solves out of five, then take the average of the three left. It is the number that decides the rankings in most cube competition events, and it is also the number cubers love to show off to each other. This guide shows you how to work out Ao5, Ao12 and Mo3 by hand, even when a solve gets a +2 penalty or a DNF.
Why not just count your fastest solve?
A single solve can be very lucky: the scramble turns out easy, or you happen to skip a step. If only the fastest solve counted, the luckiest cuber would beat the best one.
An average tells you how fast you solve most of the time. Dropping the best and worst solves means one lucky solve or one disaster cannot throw the whole result off. According to the Speedsolving Wiki, the solves left after dropping are called "counting times".
That is why a WCA competition records two results for you: single (your best single solve) and average. Each one has its own rankings and records.
How to calculate Ao5, step by step
Under WCA rules, in the "Average of 5" format a competitor does 5 solves, the best and worst are dropped, and the other 3 are averaged (Regulation 9f8, WCA Regulations).
Follow these 4 steps:
- Write down your 5 times.
- Cross out the fastest one.
- Cross out the slowest one.
- Add up the 3 times left and divide by 3.
A beginner's example: your 5 solves are 52.31, 48.90, 1:05.12, 50.47 and 47.05 seconds.
- Drop 47.05 (fastest) and 1:05.12 (slowest).
- Add: 52.31 + 48.90 + 50.47 = 151.68.
- Divide by 3: Ao5 = 50.56 seconds.
Look at the 1:05.12 solve: you got stuck somewhere, but it did not spoil your result, because it was dropped.
A real example: the 2025 World Championship final
In the 3x3 final of the 2025 World Championship, Yiheng Wang did 5 solves: 5.45, 3.80, 4.31, 3.94 and 4.43 seconds (WCA).
- Drop 3.80 and 5.45.
- 4.31 + 3.94 + 4.43 = 12.68.
- 12.68 / 3 = 4.2267, rounded to 4.23 seconds, exactly the number the WCA published.
The runner-up, Xuanyi Geng, had a better best single of 3.95 but an average of 4.49, so still finished second. Final rankings go by average, not by single.
Four moves.
One at a time.
Tap each symbol and follow one piece. This is an exercise in watching the movement.
What is Ao12 and how do you work it out?
Ao12 is the average of 12 solves. Ao12 is not a WCA competition format; cubers use it when practising at home, because 12 solves give a steadier number than 5.
It works just like Ao5: drop the 1 fastest and 1 slowest solve, then average the 10 that are left (Speedsolving Wiki).
Example: 12 practice solves (in seconds):
18.42, 20.15, 17.88, 19.30, 25.61, 18.97, 16.74, 19.85, 21.02, 18.11, 19.44, 20.68
- Drop 16.74 (fastest) and 25.61 (slowest).
- Add the other 10 solves: 193.82.
- Divide by 10: Ao12 = 19.38 seconds.
Quick trick: add all 12 solves (236.17), then take away the two dropped ones (16.74 + 25.61 = 42.35) to get 193.82. This is less likely to go wrong than adding each solve one by one after crossing some out.
How is Mo3 different from Ao5?
Mo3 means "mean of 3": the average of all 3 solves, with none dropped (Regulation 9f10). The WCA uses Mo3 for 6x6 and 7x7, because each solve on these cubes takes a long time (Regulation 9b2).
6x6 example: 2:45.30, 2:51.12, 2:39.88.
- Change to seconds: 165.30 + 171.12 + 159.88 = 496.30.
- Divide by 3: 165.43 seconds, so Mo3 = 2:45.43.
Because nothing is dropped, Mo3 is stricter: a single DNF turns the whole Mo3 into a DNF (Regulation 9f11).
How does a +2 penalty count?
A +2 solve gets 2 seconds added before you sort your times and cross any out. Under WCA rules you get a +2 when, for example:
- you start solving after inspecting for 15 seconds or more but less than 17 (Regulation A4d1);
- you stop the timer before letting go of the cube (Regulation A6c);
- the cube is exactly one move away from solved (Regulation 10e3).
Example: 30.45, 28.12 (+2), 33.80, 27.66, 29.91.
- The second solve becomes 30.12.
- Drop 27.66 and 33.80.
- 29.91 + 30.12 + 30.45 = 90.48, divided by 3: Ao5 = 30.16.
Without the penalty, the 28.12 solve would have counted and the Ao5 would be 29.49. Two penalty seconds on one solve made the average almost 0.7 seconds slower.
How does a DNF count?
A DNF (Did Not Finish) is a solve that does not count, for example when the cube is not solved, or when you start solving after more than 17 seconds of inspection (Regulations 9f4, A4d2). When working out an average, treat a DNF as the slowest possible solve.
- One DNF in an Ao5: the DNF is the worst solve, so it gets dropped. You still get an average (Regulation 9f9).
- Two or more DNFs: only one worst solve can be dropped, so the other DNF ends up among the counting times, and the whole Ao5 becomes a DNF.
Example with one DNF: 22.40, DNF, 24.10, 21.85, 23.05.
- Drop 21.85 (fastest) and the DNF (slowest).
- 22.40 + 24.10 + 23.05 = 69.55, divided by 3: Ao5 = 23.18.
Example with two DNFs: 22.40, DNF, 24.10, DNF, 23.05. After dropping one DNF, there is still a DNF among the 3 counting times, so the result is a DNF.
Ao12 works the same way: one DNF gets dropped, and two or more turn the Ao12 into a DNF.
Rounding and rankings
WCA rules have three small points worth knowing (Regulations 9f1, 9f14):
- Single solves under 10 minutes are cut off (truncated) at hundredths of a second. For example, 12.348 is recorded as 12.34.
- Averages under 10 minutes are rounded to hundredths of a second. For example, 4.2267 becomes 4.23, as in Yiheng Wang's example above.
- Two people with the same average: whoever has the better single ranks higher.
Ao50, Ao100: which number should you use at home?
For longer averages, the Speedsolving Wiki describes a common approach: drop about 5% of the best solves and 5% of the worst, rounding up (Speedsolving Wiki):
| Average | Solves | Fastest dropped | Slowest dropped | Counting solves |
|---|---|---|---|---|
| Ao5 | 5 | 1 | 1 | 3 |
| Ao12 | 12 | 1 | 1 | 10 |
| Ao50 | 50 | 3 | 3 | 44 |
| Ao100 | 100 | 5 | 5 | 90 |
Each number answers a different question:
- Ao5: the closest thing to what you would get in a competition round.
- Ao12: your "everyday" number, telling you how you are solving today.
- Ao100: the real measure of your level, because a short lucky streak can hardly pull it down.
Most cube timers show a rolling average: each time a new solve is added, the oldest one drops out. So your best Ao5 can be any 5 solves in a row from your practice session.
Get Ao5 and Ao12 worked out for you with the EasyRubic timer
You do not have to do the maths by hand every time. The EasyRubic 3x3 timer shows your best single, Ao5, Ao12 and the average for the whole session. You can turn on 15 seconds of inspection like at a competition, and mark your last solve as +2 or DNF so the averages follow the rules.
A few habits that keep your average meaningful:
- Do not delete bad solves. A bad solve is part of your level; delete it and your average looks nicer but is wrong.
- Practise in sets of 5 solves. Each set is a mini "competition round" and helps you get used to the idea that one bad solve is not the end.
- Compare your Ao12 week by week, not solve by solve. A gap of a few seconds between two solves is normal.
If you cannot solve the whole cube yet, start with the layer-by-layer step-by-step guide. To see how a real competition round works, read Rubik's Cube competitions and the WCA.
Sources
Frequently asked questions
What is Ao5?
Ao5 (average of 5) is the average of 5 solves: drop the fastest and slowest, then average the 3 left. It is the format for most WCA events, including 3x3.
How many solves does Ao12 drop?
Ao12 drops 1 fastest and 1 slowest solve, then averages the other 10.
Does one DNF make my Ao5 a DNF?
No. A single DNF counts as the slowest solve and gets dropped. Only two or more DNFs turn the Ao5 into a DNF.
What is Mo3?
Mo3 (mean of 3) is the average of all 3 solves, with none dropped. The WCA uses Mo3 for 6x6 and 7x7; a single DNF turns the Mo3 into a DNF.
Which matters more, Ao5 or single?
In most events, the rankings of a round go by Ao5. Singles have their own rankings and records too, but Ao5 shows how consistent you really are.
This information is based on competition results owned and maintained by the World Cube Association, published at worldcubeassociation.org/results as of 14.10.2026.
Cover photo: Protocoldoug / Wikimedia Commons, CC0