Knowing your squares by heart makes percentages, roots and algebra much quicker. This test asks ten square questions at a time: Easy covers 2² to 15², Medium 11² to 30², and Hard 21² to 50².

Easy Medium Hard

Squares of 11 to 30.

Start 10 questions

The squares from 1 to 20 are 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256, 289, 324, 361, 400. Use the chart to check yourself, then try the tricks below for the bigger ones, such as numbers ending in 5 or close to 50.

Squares from 1 to 50

Tricks for squaring numbers fast

• Numbers ending in 5: multiply the tens digit by the next number up, then write 25 after it. For 65²: 6 × 7 = 42, so 65² = 4225. For 35²: 3 × 4 = 12, so 35² = 1225. For 85²: 8 × 9 = 72, so 85² = 7225.
• Split the number into tens and units and use (a + b)² = a² + 2ab + b². For 23²: 20² + 2 × 20 × 3 + 3² = 400 + 120 + 9 = 529.
• Numbers near 50: 48² = 50² − 2 × 50 × 2 + 2² = 2500 − 200 + 4 = 2304, and 52² = 2500 + 200 + 4 = 2704.
• Each square is the previous square plus the next odd number. Since 14² = 196, 15² = 196 + 29 = 225.
• A square always ends in 0, 1, 4, 5, 6 or 9, never in 2, 3, 7 or 8. If your answer ends in 7, check it again.
• Memorise the squares to 20 first, then the round ones: 25² = 625, 30² = 900, 40² = 1600 and 50² = 2500.

Frequently asked questions

What are the squares from 1 to 20?

1² = 1, 2² = 4, 3² = 9, 4² = 16, 5² = 25, 6² = 36, 7² = 49, 8² = 64, 9² = 81, 10² = 100, 11² = 121, 12² = 144, 13² = 169, 14² = 196, 15² = 225, 16² = 256, 17² = 289, 18² = 324, 19² = 361, 20² = 400.

What is 25 squared?

25² = 625. It ends in 5, so use the rule: 2 × 3 = 6, then write 25 after it, giving 625.

How do you square a number ending in 5?

Numbers ending in 5: multiply the tens digit by the next number up, then write 25 after it. For 65²: 6 × 7 = 42, so 65² = 4225. For 35²: 3 × 4 = 12, so 35² = 1225. For 85²: 8 × 9 = 72, so 85² = 7225.

What is the difference between a square and a square root?

Squaring multiplies a number by itself: 12² = 144. A square root goes the other way: √144 = 12. After this test, try the Square Roots Test.

How is the speed maths test scored?

Each test has 10 questions. Answer 8 or more correctly to pass. Your time is recorded for the whole test, and your best time for each test and level is saved on your own device, so you can try to beat it.

More speed maths tests

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• 12 Times Table Test
• Speed Maths Test
• All speed maths tests
• Times tables chart and tests (2 to 30)