Is mental math practice only for kids?

No. The tricks here are useful for teens and adults too, for example for tips, discounts and quick checks at work.

Can I print the drills?

Yes. Every trick has a free printable sheet with an answer key on the printable drills page.

Pick a level and take a 1 minute drill, or open a trick below to learn how it works first. Each level mixes the tricks at or below it.

Choose a test

How long?

Type the answer. Correct answers move on by themselves. Press Enter to skip a wrong one.

Add the tens first, then the ones. No carrying on paper.

Times 10, then halve it. 48 × 5 = 480 ÷ 2 = 240.

Times 10, then take away the number once. 7 × 9 = 70 − 7 = 63.

For 2-digit numbers, put the sum of the digits in the middle. 53 × 11 = 583.

Double it, then divide by 10. 85 ÷ 5 = 170 ÷ 10 = 17.

Take every digit from 9 and the last one from 10. 1000 − 374 = 626.

Split into tens and ones, multiply both, add. 34 × 6 = 180 + 24 = 204.

Halve one number and double the other until it gets easy. 16 × 25 = 8 × 50 = 400.

Divide by 4, then times 100. 36 × 25 = 9 × 100 = 900.

10% moves the point, 5% is half of that, 20% is double. Handy for tips and discounts.

Multiply the first digit by the next number up, then write 25. 65² = 42 then 25 = 4225.

Learn one trick at a time. Read how it works, then drill it for a minute.
Once a trick feels automatic, move up a level so it stays sharp alongside the new ones.
A minute a day is enough. The results show your last scores so you can see the progress.

Is mental math practice only for kids?: No. The tricks here are useful for teens and adults too, for example for tips, discounts and quick checks at work.
Can I print the drills?: Yes. Every trick has a free printable sheet with an answer key on the printable drills page.