Decimal To Fraction Converter
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How to Use This Decimal To Fraction Converter
Decimals feel friendly on a calculator display, but homework often wants a simplified fraction—and typing 0.375 into a search bar does not tell you whether the answer should be 3/8 or 375/1000. This converter accepts standard decimals, scientific notation, and long "almost repeating" strings, then prints a reduced fraction and a mixed number when the value is bigger than one.
- Type your decimal in the input field—examples include 0.125, 1.5, or 1e-2.
- Leave Simplify fraction checked for lowest terms, or uncheck it to see the raw "multiply by 10ⁿ" form from the typed digits.
- Press Convert. The main line shows the improper fraction; a mixed-number line appears when the value exceeds one and is not a whole integer.
- Cross-check the other way. Verify with the Fraction To Decimal Calculator or combine results in the Fraction Calculator.
Decimal To Fraction Formulas and Practical Applications
Think of a terminating decimal as counting how many tenths, hundredths, or thousandths you have—the denominator names the smallest slice size implied by the last digit.
Terminating decimals
0.abc… = abc… / 10ⁿ
Three digits after the point means denominator 1000: 0.625 = 625/1000 = 5/8 after dividing by GCD 125. That is the same move you learn in middle school before reducing.
Simplification
Lowest terms: divide numerator and denominator by GCD
With Simplify fraction checked, the engine applies GCD reduction automatically. Unchecked, you see the unreduced ratio built directly from the decimal digits—useful when a teacher wants the 625/1000 step shown explicitly.
Repeating and long-digit inputs
True repeating decimals need infinite digits; calculators show finite approximations. A long string like many threes often resolves to 1/3 when simplified. For very small values in scientific form, pair this tool with the Scientific Notation Calculator.
Standard Units and Conversion Tables
Common decimal-to-fraction pairs you will see in measurements and tests:
| Decimal | Fraction (simplified) | Mixed (if > 1) |
|---|---|---|
| 0.25 | 1/4 | — |
| 0.375 | 3/8 | — |
| 0.625 | 5/8 | — |
| 1.5 | 3/2 | 1 1/2 |
| 2.75 | 11/4 | 2 3/4 |
Browse all math calculators for related conversion tools.
Frequently Asked Questions
What is 0.625 as a fraction?
5/8. Write 625/1000, then divide top and bottom by 125.
How do you simplify a fraction from a decimal?
Clear the decimal with a power of ten, then divide numerator and denominator by their GCD. Keep Simplify fraction checked to skip manual reduction.
Can I enter scientific notation decimals?
Yes—formats like 1.5e-2 or 4.5e4 parse correctly before conversion.
Why does 0.33333333333333 become 1/3?
That finite string approximates the repeating decimal for one-third. The rational engine maps it to the exact fraction 1/3 when simplified.
When does a mixed number line appear?
When absolute value exceeds one and the result is not a whole integer—for example 1.5 shows 3/2 on the main line and 1 1/2 below.
Disclaimer. RapidRatio is informational only—not academic or professional advice. Verify results with your instructor when graded work depends on a specific method.