Column addition practice
Practice adding numbers in columns, with 1 to 5 digits in each number. Each problem appears on squared paper, one digit per square, so ones sit under ones and tens under tens. It's free and needs no sign-up.
How to practice
- Choose how many digits the top and bottom numbers have.
- Press New problem and work out the sum, on paper if you like.
- Type the answer and press Check.
The answer can be typed from left to right, or from right to left, starting with the ones, the way sums are written on paper: pick an arrow under Write the answer. The answer box is always one square wider than the longer number, so its size never gives the answer away.
Which level to choose
| Digits (top + bottom) | Example | Usually practiced around age |
|---|---|---|
| 1 + 1 | 7 + 5 | 6 to 7 |
| 2 + 1 and 2 + 2 | 47 + 38 | 7 to 8 |
| 3 + 2 and 3 + 3 | 365 + 278 | 8 to 9 |
| 4 and 5 digits | 4806 + 2795 | 9 to 11 |
School years differ from country to country, so take the ages as a rough guide. A good level is one where most answers are right but your child still has to think.
An example
| 4 | 7 | |
| + | 3 | 8 |
| 8 | 5 |
7 plus 8 is 15: write 5 in the ones and carry 1 to the tens. Then 4 plus 3, plus the 1 carried, is 8. The answer is 85.
Common slips
- Forgetting the carried 1. Writing it small above the next column helps.
- Starting on the left. Column addition starts with the ones, on the right.
- A carry out of the last column. In 76 + 58 the answer has a digit more than either number: 134.
Questions
Is it free?
Yes. There's no sign-up and no limit on the number of problems.
Are the coins saved?
Yes, in this browser on this device. They aren't sent anywhere, so they don't follow your child to another device, and clearing the browser's data removes them. Family accounts, coming soon, will keep them safe.
Can my child use a keyboard?
Yes. The number keys type digits, Backspace deletes the last one, Escape clears the answer and Enter checks it.
More practice: subtraction, multiplication and division.