Online math game

Addition and subtraction: problems within 10, 20 and 100

Also known as: addition and subtraction problems, addition and subtraction within 10, addition and subtraction within 100

Solve addition and subtraction problems and type the answer: it’s checked automatically. First within 10, then within 20 with crossing over ten, then up to 100. A round lasts two minutes, and you can play 10 minutes a day without signing up.

Go to the game ↓
  • 2 minutesper round
  • 4 levelsfrom 10 to 100
  • No sign-up10 minutes a day
  • Progress30-day chart
What it trains

Why use this trainer

Addition and subtraction are the foundation of all mental math. The trainer starts with the simplest problems and moves on only when you solve the current ones confidently. The answer is never negative.

In “Quick Math” numbers go up to 400 and a problem can have three numbers. Here it’s calmer: two numbers and nothing above 100. Once you sign up, every round is saved and your account shows a chart.

  • Your child is learning to countProblems that fit their level, without big numbers
  • You stumble when a sum crosses tenYou have to count up for 8 + 7
  • “Quick Math” still feels hardYou’d like to start with something simple
  • You want a short warm-upTwo minutes of problems

Mental arithmetic

Addition and subtraction without fingers or paper.

Crossing over ten

Level 2 is all about problems like 8 + 7 and 15 − 8.

Speed

The faster you answer, the more problems you solve in two minutes.

Accuracy

A mistake costs a point, so guessing doesn’t pay.

Rules

How to play

  1. Start

    Press “Start”. Five problems appear on the screen and a two-minute timer begins.

  2. Answer

    Type the answer with the on-screen buttons or the number keys on your keyboard. The answer is checked automatically once all its digits are typed.

  3. Score

    A correct answer earns a point and a mistake takes one away, but your score never drops below zero. If you get it wrong, the correct answer appears next to it.

  4. Level

    Problems come in sets of five. If you get 4 out of 5 right in a checkpoint set, the level goes up; with fewer, it may go down.

  5. Finish

    After two minutes the round ends. You’ll see your score, correct answers, mistakes and top level.

Play online

Addition and subtraction online

Press “Start” and type your answers. Without sign-up you get 10 minutes of play a day.

Addition and Subtraction

Addition and subtraction problems: up to 10, then 20, then 100. Get them almost all right and they get harder.

Free play left today without signing up: 10 min

Method

How the levels work

The levels follow the order in which kids learn arithmetic in elementary school: first within 10, then within 20 with crossing over ten, then within 100. On level 4 both numbers have two digits. Every problem has two numbers, and the answer is from 0 to 100.

Once this trainer feels easy, move on to “Quick Math” with three-number problems. For multiplication, try “Times Tables”.

up to 10Level 1Addition and subtraction within 10.
up to 20Level 2Addition and subtraction crossing over ten.
up to 100Levels 3 and 4Numbers up to 100; on level 4 both have two digits.
Who it’s for

Which ages

Adults

An easy warm-up or a first step before “Quick Math”.

Kids

Suitable from age 6 if your child knows the digits: level 1 is addition and subtraction within 10, and difficulty rises only after confident answers. Not yet part of the “Kids” collection.

60+

Calm problems with familiar numbers; you type answers with on-screen buttons. Not part of the “60+” collection.

Program finder

Get your program in a minute

Answer 4 questions and we’ll put together a daily program of 5 trainers. We’ll email you the full 2-week plan.

Question 1 of 4

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Questions

Frequently asked questions

Are there negative answers?

No. The smaller or equal number is always subtracted from the larger one, so the answer is from 0 to 100.

How is it different from “Quick Math”?

In “Quick Math” numbers go up to 400 and problems can have three numbers. Here there are always two numbers and nothing above 100.

How is my answer checked?

Automatically, with no Enter key: as soon as you’ve typed as many digits as the correct answer has. You can erase a digit until the whole answer is typed.

Can I type answers on the keyboard?

Yes. Type digits on your computer keyboard; Backspace erases the last digit. On a phone you get buttons on the screen.

Do I need to sign up?

No, you can play 10 minutes a day right away. Free sign-up lets you keep playing, save your results, track your progress and unlock the daily workout.

Save your results and track your progress

Free sign-up: round history, a chart by skill and a daily workout of 5 exercises. No credit card needed.

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