Mental math practice online

Mental math drills at the right level

This tool asks one calculation at a time and marks each answer straight away. It works for a child learning to add within 10 as well as for an adult who wants to stay sharp. Everything runs in your browser with no account, and best scores stay on your device.

The "Level" menu has two groups. "The four operations" mixes addition, subtraction, multiplication and division within a number range: up to 10 (kindergarten or Year 1), up to 20 (first grade or Year 2), up to 100 (grades 2 to 5) or up to 1,000 (middle school and adults). Answers never go past the chosen limit and every division comes out even. "Targeted drills" practise a single skill: number bonds to 10 or 100, 2-digit × 1-digit, squares from 2 to 20, simple percentages and simple fractions.

How to use it

1. Pick a level, then tick the operations you want (at least one).
2. Pick a mode: "10 questions", "20 questions" or "50 questions" for a fixed set, or "60 seconds" or "120 seconds" to answer as many as you can against the clock.
3. Press "Start!" (or the space bar). Type your answer and press Enter; on a phone or tablet, use the number pad shown under the question.
4. A correct answer moves on by itself. A wrong one shows "✗ Wrong", the right answer and a tip worked out with the numbers from the question. In timed mode the clock pauses while you read the tip.
5. The summary shows your score, your longest streak, the average time per answer and the list of mistakes to review. "Replay only my mistakes" runs those questions again.

"Print a worksheet with answers" gives you a sheet with the same settings and an answer key on a second page.

Strategies that save time

• Round and adjust: 98 + 57 = 100 + 57 − 2 = 155. In the same way, 83 − 29 = 83 − 30 + 1 = 54.
• Bridge through ten: 8 + 5 = 8 + 2 + 3 = 10 + 3 = 13.
• Number bonds: knowing the pairs that make 10 (3 + 7, 4 + 6…) lets you reach 100 in two jumps: 63 + 7 = 70, then 70 + 30 = 100, so the answer is 37.
• × 9 and × 11: 7 × 9 = 70 − 7 = 63. For 47 × 11, split the digits 4 and 7, put their sum (11) in the middle, keep the 1 and carry 1 onto the 4: 47 × 11 = 517.
• Partitioning: 47 × 6 = 40 × 6 + 7 × 6 = 240 + 42 = 282.
• Friendly numbers: 25 × 16 = 25 × 4 × 4 = 100 × 4 = 400, because 25 × 4 = 100.
• Percentages and fractions: 25% of 80 is a quarter of 80, which is 20; 3/4 of 20 = 20 ÷ 4 × 3 = 15.

Practising well

Five minutes a day beats one long session a week. Start with 10 questions to find the right level: above 9 out of 10, move up; below 6, step back. Then use "60 seconds" to build fluency with math facts, and always finish by replaying your mistakes.

Frequently asked questions

What age is this for?

From about 5 or 6 with "Numbers up to 10" and addition only. The levels then follow the primary years and middle school, up to percentages and squares that adults use every day too.

How is the average time worked out?

It is the time spent answering divided by the number of answers. The moment when the correction is on screen is not counted.

Where are best scores kept?

In the browser on your device, for each combination of level, operations and mode. Nothing is sent anywhere; "Clear best scores" deletes them.

Do the questions change every time?

Yes, they are drawn at random for each drill and each printed worksheet, never the same question twice in a row. Only "Replay only my mistakes" repeats questions, in a different order.