The three forms
The same value can be written as a fraction, a decimal, and a percent: 4/5 = 0.8 = 80%.
80% as a Fraction
Explained step by step — with reference tables, charts, and a live converter.
80% as a fraction is 4/5 (in lowest terms).
Convert any value
Result
Step by step
1. Write it over 100
Percent means “per hundred”, so 80% = 80/100.
2. Reduce
The greatest common divisor of 80 and 100 is 20, so 80/100 = 4/5.
The fraction visualized
4 of 5 parts shaded
On the number line
This value: 0.8
Common fractions compared
Fraction ↔ Decimal ↔ Percent
| Fraction | Decimal | Percent |
|---|---|---|
| 1/2 | 0.5 | 50% |
| 1/3 | 0.3333 | 33.33% |
| 2/3 | 0.6667 | 66.67% |
| 1/4 | 0.25 | 25% |
| 3/4 | 0.75 | 75% |
| 1/5 | 0.2 | 20% |
| 2/5 | 0.4 | 40% |
| 1/8 | 0.125 | 12.5% |
| 3/8 | 0.375 | 37.5% |
| 5/8 | 0.625 | 62.5% |
| 7/8 | 0.875 | 87.5% |
| 1/10 | 0.1 | 10% |
| 1/16 | 0.0625 | 6.25% |
About fractions, decimals, and percents
Fractions, decimals, and percents are three ways of writing the same proportion. A fraction is the ratio of two whole numbers, a decimal is the result of dividing them, and a percent is that same number expressed per hundred.
These conversions are pure math and never change — the results on this page are exact, not rounded (except where rounding is explicitly shown).
Related conversions
Where fraction-decimal conversions are used
Fraction-to-decimal conversions help with measurements, cooking, and finance — turning halves, thirds, and eighths into decimals and back.
- Some fractions are exact decimals (1/4 = 0.25), while others repeat forever (1/3 = 0.333…).
- A fraction terminates as a decimal only when its denominator has no prime factors other than 2 and 5.
- Imperial tools often use sixteenths of an inch, so 3/16 in = 0.1875 in is a common conversion.
Frequently asked questions
What is 80% as a Fraction?
80% as a fraction is 4/5 (in lowest terms).
How do you convert 80% to a fraction?
Write 80% as 80/100, then reduce the fraction fully to 4/5.
What is 80% as a decimal?
80% equals 0.8. Divide the percentage by 100.
What does “in lowest terms” mean?
A fraction is in lowest terms (simplest form) when the numerator and denominator share no common factor other than 1. For example, 6/8 can still be reduced, but 3/4 cannot.
Convert more
The fraction & decimal converter covers decimals, fractions, and percents with exact step-by-step solutions.