Factors and multiples: what is the difference?

Factors divide into a number exactly; multiples are what you get when you multiply it. The factors of 12 are 1, 2, 3, 4, 6 and 12; the multiples of 12 are 12, 24, 36 and so on forever. This page shows how to find every factor in pairs, uses factor rainbows, and has a factor finder for any number.

The difference between factors and multiples

Factors of 12Multiples of 12
MeaningNumbers that go into 12Numbers 12 goes into
List1, 2, 3, 4, 6, 1212, 24, 36, 48, …
How manyA short, complete listEndless
Size12 or smaller12 or bigger

Memory aid: factors fit in, multiples multiply out.

How to find all the factors of a number

  1. Start with 1 × the number.
  2. Try 2, 3, 4… in order. When one divides exactly, write the pair: 2 × 12, 3 × 8, 4 × 6 for 24.
  3. Stop when the pairs meet: after 4 × 6, the next would be 6 × 4, which you already have.
1234681224
Factor rainbow for 24: each arch is a pair.

Factor finder

Any number up to 10,000: factor pairs, all factors, prime or composite, and the first multiples.

How to find multiples

Skip count, or multiply by 1, 2, 3, 4…: the multiples of 7 are 7, 14, 21, 28, 35… Every number is a multiple of itself, and a multiple of each of its factors.

Common mistakes

Factors of 12: 12, 24, 36Gave multiples.Fix: factors are 12 or smaller.
Factors of 36 without 6Missed the square pair 6 × 6.Fix: list in pairs and stop when they meet.
Forgot 1 and the number itselfListed only the ‘middle’ factors.Fix: every number has 1 and itself as factors.
“0 is a multiple of nothing”Unsure about zero.Fix: in grade 4, multiples start from the number itself: 7, 14, 21.

How to teach it at home

Rectangle builder

With 24 tiles, how many different rectangles can you make? Each is a factor pair.

Fizz buzz

Clap on multiples of 3, stamp on multiples of 5.

Party bags

24 sweets into equal bags: what bag sizes work?

By grade

Worksheets and practice

Last reviewed

Questions parents ask

What is the difference between a factor and a multiple?

A factor divides into a number exactly; a multiple is the result of multiplying a number. 3 is a factor of 12, and 12 is a multiple of 3.

How do you find all the factors of a number?

Test 1, 2, 3 and so on, writing each factor pair, and stop when the pairs meet in the middle.

Is a number a factor of itself?

Yes. Every number has 1 and itself as factors.

How many multiples does a number have?

Infinitely many: you can keep multiplying forever.

What grade learns factors and multiples?

Grade 4 (4.OA.B.4), with numbers up to 100.