Every fraction is a division problem waiting to happen: the numerator divided by the denominator gives the exact decimal value. This chart covers the fractions that show up most in measurements, recipes, and everyday math, from simple halves down to sixteenths.
Halves through eighths
| Fraction | Decimal |
|---|---|
| 1/2 | 0.5 |
| 1/4 | 0.25 |
| 3/4 | 0.75 |
| 1/8 | 0.125 |
| 3/8 | 0.375 |
| 5/8 | 0.625 |
| 7/8 | 0.875 |
Sixteenths
Sixteenths are the standard precision on most tape measures, which is why they’re worth memorizing on their own.
| Fraction | Decimal | Fraction | Decimal |
|---|---|---|---|
| 1/16 | 0.0625 | 9/16 | 0.5625 |
| 3/16 | 0.1875 | 11/16 | 0.6875 |
| 5/16 | 0.3125 | 13/16 | 0.8125 |
| 7/16 | 0.4375 | 15/16 | 0.9375 |
Thirds and sixths (repeating decimals)
| Fraction | Decimal |
|---|---|
| 1/3 | 0.3333… |
| 2/3 | 0.6667 |
| 1/6 | 0.1667 |
| 5/6 | 0.8333 |
Thirds and sixths never terminate — their decimals repeat forever because 3 isn’t a factor of any power of 10. The values above are rounded to four decimal places, which is more precision than most real-world tasks need.
Fifths and tenths
| Fraction | Decimal |
|---|---|
| 1/5 | 0.2 |
| 2/5 | 0.4 |
| 3/5 | 0.6 |
| 4/5 | 0.8 |
| 1/10 | 0.1 |
| 7/10 | 0.7 |
Why some fractions terminate and others repeat
A fraction’s decimal form terminates cleanly only if its denominator (once fully simplified) has no prime factors other than 2 and 5 — which is exactly why halves, quarters, eighths, sixteenths, fifths, and tenths all convert to clean decimals, while thirds, sixths, sevenths, and ninths repeat forever.
1/8 → denominator 8 = 2 × 2 × 2 → only 2s → terminates: 0.125
1/6 → denominator 6 = 2 × 3 → has a 3 → repeats: 0.1666...
For any fraction not listed here, or to convert a mixed number, use the fraction to decimal calculator. To go the other direction and turn a decimal back into a fraction, try the decimal to fraction calculator.