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Fraction to Decimal Calculator
Use this fraction to decimal calculator to turn any fraction into a decimal in seconds. Enter the numerator and denominator — and a whole number if it is a mixed number — and you get the decimal, the matching percent, and the simplified fraction, with repeating decimals shown clearly so you know exactly when the digits go on forever.
The whole number is optional — leave it blank for a plain fraction like 3/8. For a mixed number such as 1 3/4, enter 1 as the whole number.
How it works
Converting a fraction to a decimal is one division: divide the numerator by the denominator. The numerator is the top number — how many parts you have. The denominator is the bottom number — how many equal parts the whole is split into. For a mixed number, convert the fraction part the same way, then add the whole number on top.
Numerator: the number of parts you are counting. It can be any whole number, and it can be larger than the denominator — that just gives a decimal bigger than 1, like 7/4 = 1.75. A numerator of 0 gives a decimal of 0, whatever the denominator is.
Denominator: the number of equal parts in one whole. It can never be 0, because dividing by zero has no answer — the calculator will tell you so if you try. Larger denominators mean smaller slices, so 1/100 is a much smaller decimal than 1/2.
Whole number (optional): only for mixed numbers like 2 1/2. Leave it blank or set it to 0 for an ordinary fraction. If you enter a negative whole number, the fraction part is subtracted from it, matching how mixed numbers are normally written.
Once the decimal is found, the percent is the decimal times 100 — move the decimal point two places to the right and add a percent sign. The simplified fraction comes from dividing the numerator and denominator by their greatest common factor, so 6/8 becomes 3/4 and 10/25 becomes 2/5. If the fraction is already in lowest terms, it stays as it is.
Repeating decimals
Some fractions give decimals that never end. Divide 1 by 3 and the 3s keep coming forever: 0.3333... The calculator spots this and marks the repeating part with a bar over the digits, so 1/3 shows as 0.3 with a bar over the 3, and 2/3 shows as 0.6 with a bar over the 6. Longer cycles get the same treatment: 1/7 = 0.142857142857... shows as 0.142857 with a bar over 142857, because those six digits repeat.
Whether a fraction terminates or repeats depends on its denominator once the fraction is simplified. If the denominator's only prime factors are 2 and 5 — denominators like 2, 4, 5, 8, 10, 16, 20, and 25 — the decimal stops. Any other prime factor in the denominator, such as 3, 6, 7, 9, or 11, makes the decimal repeat. That is why 3/8 terminates at 0.375 but 1/3 repeats forever, and it is also why money, which is measured in hundredths, always uses terminating decimals.
Worked example
Convert 3/8 to a decimal, a percent, and its simplest form.
Step 1: Divide the numerator by the denominator: 3 ÷ 8 = 0.375. The division ends cleanly — 8 goes into 3.000 exactly 0.375 times — so this is a terminating decimal.
Step 2: Turn the decimal into a percent by multiplying by 100: 0.375 × 100 = 37.5%.
Step 3: Simplify the fraction. The greatest common factor of 3 and 8 is 1, so 3/8 is already in lowest terms and stays 3/8.
Try it yourself: enter 3 as the numerator and 8 as the denominator, with the whole number left blank. The tool gives exactly the same answer — 3/8 = 0.375, 37.5%, simplified fraction 3/8 — and the breakdown table shows the division, the percent step, and the simplification side by side.
For a repeating example, try 1/3. The tool shows 0.333333... with a bar over the 3, written as 0.(3), and 33.33%. And for a mixed number, try whole number 1, numerator 3, denominator 4: the tool gives 1.75, which is 175%, simplified as the mixed number 1 3/4.
FAQ
How do I convert a fraction to a decimal?
Divide the numerator by the denominator. For example, 3 divided by 8 is 0.375, so 3/8 equals 0.375. This calculator does the division for you, and it also shows the percent and the simplified form of the fraction.
What is a repeating decimal, and how is it shown here?
A repeating decimal is a decimal whose digits repeat forever, like 1/3 = 0.3333... The calculator detects the repeating part and shows it with a bar over the repeating digits, for example 0.3 with a bar over the 3, and also writes it as 0.(3). The rounded decimal value is shown too, so you can copy a plain number when you need one.
How do I convert a mixed number to a decimal?
Enter the whole number in the whole number box, then the numerator and denominator of the fraction part. For example, 1 3/4 becomes 1 + 0.75 = 1.75. If the whole number box is left empty or set to 0, the calculator treats the input as a plain fraction.
What is the difference between a terminating and a repeating decimal?
A terminating decimal stops, like 3/8 = 0.375. A repeating decimal goes on forever, like 1/3 = 0.333... A fraction in lowest terms terminates only when its denominator has no prime factors other than 2 and 5 — denominators like 2, 4, 5, 8, 10, and 20. Any other denominator, such as 3, 6, 7, or 9, gives a repeating decimal.
Can I convert a decimal back to a fraction?
Yes. This page converts fractions to decimals, and the reverse tool — the decimal to fraction calculator — converts decimals back to fractions. You will find it in the related tools below. Use the decimal to fraction calculator when you start with a number like 0.75 and want the fraction 3/4.