How many sums can you do in your head in 30 seconds? A calculation sprint that gets harder the better you do
How it works
One expression appears at a time; type the answer on the keypad below. The moment your input matches, it jumps to the next question โ no submit button, no Enter. When the 30 seconds are up, your score is the number you solved.
- Press START: the clock begins and you get single-digit addition.
- Tapping digits builds your answer. Match the result and the display flashes green and moves on instantly.
- If your input has as many digits as the answer but the wrong value, it counts as a miss โ the display flashes pink, shows the answer briefly, and a new question appears. Use the delete key to fix a mistyped digit before that.
- Every five correct answers raises the level: two-digit addition, then times tables, then two-digit multiplication and division, then three-term sums.
- On a computer the number keys and Backspace work too.
Rules and scoring
| Time limit | 30 seconds total (no per-question clock) |
|---|---|
| Levels | 0-4 single-digit addition ยท 5-9 two-digit ยฑ single-digit ยท 10-15 two-digit sums and times tables ยท 16-23 two-digit multiplication and division ยท 24+ adds three-term sums |
| Checking | Automatic as soon as your input equals the answer |
| A miss | Score unchanged, new question after 0.8 s. You only lose time |
| Answers | Always non-negative integers โ no negatives, decimals or fractions |
| Score | Correct answers in 30 seconds. You need 5 to submit |
| Grades | 25+ "no calculator needed", 18-24 "top tier", 12-17 "above average", below that "average" |
How to get faster
- Start from the tens. 47 + 38 is 40+30=70, then 7+8=15, so 85. Working right-to-left as you would on paper costs you the carry.
- Make a round number. Turn 47 + 38 into (47+3) + 35 = 50 + 35.
- Split the multiplication. 23 ร 7 is 20ร7=140 plus 3ร7=21, so 161.
- Subtract by adding up. For 120 โ 38, ask how far 38 is from 120 (2 then 80).
- Know your times tables cold. Questions 16-23 are multiplication and division; hesitating there is what separates scores.
- Move on when stuck. A miss costs time, not points, so nothing is worse than staring at one question.
Frequently asked questions
I typed the answer but nothing happened
Your input has to match exactly. If it has the same number of digits as the answer but a different value, it is scored as a miss right away โ use the delete key before that if you mistyped.
Is there a submit button?
No. Answers are checked automatically so that all 30 seconds go into solving.
Are there negative or decimal answers?
Never. Subtraction always takes the smaller number from the larger, and divisions come out exact.
My record disappeared
The personal best lives in this browser, so a new device or cleared site data resets it. Submitted scores stay on the server.
Related tests
- Schulte Table โ find 1 to 25 in order: attention and field of view.
- Stroop Test โ pick the ink colour, not the word.
- Reaction Time Test โ raw reflexes with no arithmetic.
- Digit Span Memory Test โ holding numbers rather than crunching them.