Fractions to Percentages
💡Learn the handful of building blocks: 1/2 is 50%, 1/4 is 25%, 1/5 is 20%, 1/8 is 12.5%. Most fractions are just multiples of these.
Try it — turn a fraction into a percent
liveDivide top by bottom, then multiply by 100.
- 1
Divide top by bottom
3 ÷ 8 = 0.38
- 2
Multiply by 100
0.38 × 100 = 37.5%
⏱️ Practice against the clock
A worked example
3/8: one eighth is 12.5%, so three eighths is 3 × 12.5 = 37.5%.
Learn a few by heart, build the rest
A handful of fractions cover most of daily life: 1/2 is 50%, 1/4 is 25%, 1/5 is 20%, 1/8 is 12.5%. Know those cold and you are mostly just counting copies.
3/8 is three 1/8s, so 3 × 12.5 = 37.5%. 2/5 is two 1/5s, so 40%. You are not really dividing, you are adding up blocks you already recognise.
When the bottom number is ugly
If a fraction will not build from the usual suspects, go back to basics: top divided by bottom, times 100. 5/16 comes out to 0.3125, so 31.25%.
Worth filing away that thirds and sixths repeat: 1/3 is 33.3%, 1/6 is 16.7%. Round them on sight instead of chasing the decimal forever.
Questions people ask
Which fractions are worth memorising? ▾
The eighths and fifths cover most of what you will meet: 1/8 = 12.5%, 1/5 = 20%, plus the obvious 1/2, 1/4 and 3/4. Everything else builds from these.
What about a fraction with an awkward denominator? ▾
Divide the top by the bottom to get a decimal, then multiply by 100. 5/16 is 0.3125, which is 31.25%.