How do you convert a decimal to a percent?

Multiply the decimal by 100 and add a percent sign. For example, 0.25 multiplied by 100 equals 25, so 0.25 as a percentage is 25%. This works because a percentage is simply a number expressed as a fraction of 100, and multiplying by 100 converts the decimal fraction into that same scale.

What is 0.5 as a percentage?

0.5 as a percentage is 50%. You get this by multiplying 0.5 by 100, which gives 50, then adding the percent sign. This is the same as saying 0.5 is half, and half of 100% is 50%.

How do I convert a decimal to a percent without a calculator?

Move the decimal point two places to the right and add a percent sign. For example, 0.125 becomes 12.5% (the decimal point moves from between the 0 and 1 to between the 12 and 5). This shortcut works because multiplying by 100 is the same as shifting the decimal point two places right.

Decimal to Percent Converter

This decimal to percent converter turns any decimal number into a percentage instantly, without you needing to work out the multiplication by hand. Percentages are just decimals expressed as parts per hundred, and being able to convert between the two quickly matters whenever you are checking interest rates, GST calculations, exam or survey results, discounts, or probability figures. To use it, type your decimal into the input box and choose how many decimal places you want the answer rounded to, from a whole number up to four decimal places. The calculator then returns three results: the rounded percentage based on your chosen precision, the exact percentage before any rounding is applied, and the equivalent value written as a simplified fraction. Below the results you can see the full working, showing your decimal multiplied by 100 to reach the answer, plus the shortcut method of moving the decimal point two places to the right and adding a percent sign, worked through with your own figure as the example. A quick reference table alongside the input also lists common decimal to percentage pairs, such as 0.25 to 25% and 0.5 to 50%, so you can sense-check your result at a glance. Because this is a straightforward mathematical conversion rather than an estimate, the figures shown are exact for the decimal you enter, subject only to the rounding option you select.

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Reviewed July 2026 Standard mathematical conversion, verified against manual calculation.

1. Enter Your Decimal

Decimal number

Round percentage to (decimal places)

2. Quick Reference

Decimal	Percent

Your Result

Percentage
-
Rounded as selected

Exact Percentage

Before rounding

As a Fraction

Simplified

Working

Your decimal-

Multiply by100

Result-

Shortcut Method

Step 1Move decimal point 2 places right

Step 2Add a percent sign

Example-

Summary: Enter a decimal above.

How to Convert a Decimal to a Percent

A percentage is simply a way of expressing a number as a fraction of 100. Because a decimal is already a number scaled between whole numbers, converting it to a percentage only requires multiplying by 100 and adding the percent sign. This is one of the simplest conversions in maths, but it comes up constantly in everyday life, from working out discounts and interest rates to reading survey results and exam scores.

The Formula

The formula is straightforward:

Percent = Decimal x 100

For example, to convert 0.25 to a percentage: 0.25 x 100 = 25, so 0.25 is 25%. To convert 1.5 to a percentage: 1.5 x 100 = 150, so 1.5 is 150%. Decimals greater than 1 simply become percentages greater than 100%.

The Shortcut: Moving the Decimal Point

Since multiplying by 100 is the same as shifting the decimal point two places to the right, you can convert decimals to percentages without a calculator. Take 0.375: move the decimal point two places right to get 37.5, then add the percent sign to get 37.5%. If the decimal has fewer than two digits after the point, add zeros as placeholders. For example, 0.4 becomes 40% (treated as 0.40, then shifted to 40).

Common Decimal to Percent Conversions

Decimal	Percentage
0.01	1%
0.1	10%
0.25	25%
0.5	50%
0.75	75%
1.0	100%
1.5	150%
2.0	200%

Why This Matters

Decimal to percent conversions show up in interest rates on loans and savings accounts, GST and tax calculations, sports and exam statistics, and probability. Understanding the relationship between decimals, fractions and percentages helps you quickly sense-check numbers you see in everyday finance and reporting, without needing to reach for a calculator every time.

Related Calculators

Maths and Stats Calculators: the full hub of maths and statistics tools.
Fraction to Decimal Calculator: convert fractions into decimal form.
Decimal to Fraction Calculator: convert decimals into simplified fractions.
Percent to Fraction Calculator: convert percentages into fractions.
Percentage Calculator: general purpose percentage working.

Sources: Standard mathematical definition of percentage as parts per hundred. New Zealand Curriculum, Mathematics and Statistics learning area (education.govt.nz).

This calculator performs a standard decimal to percentage conversion. Results are exact based on the number you enter, subject to the rounding option you select.