Percent To Decimal Calculator

What this calculator does

So, you have a percentage like 50% and you want it as a plain decimal, 0.5. This tool divides the percent by 100 and gives you the decimal, showing up to four decimal places so small percentages stay accurate.

There is one box, for the percent. Type the number and it returns the decimal.

How to use it

1. Type the percent (just the number, without the % sign).
2. Press Calculate.

It takes zero and positive percentages, the everyday case of turning a rate like 7% into the 0.07 you can compute with.

Dividing by 100 slides the point two places left

Percent means by the hundred, so a percentage is a number of hundredths. To get its plain value you divide by 100, and dividing by 100 has a tidy shortcut: slide the decimal point two places to the left. 50% becomes 0.50, 7% becomes 0.07, and 125% becomes 1.25. The digits do not change, only where the point sits.

The method it uses

Divide the percent by 100. That is the entire conversion. 50 divided by 100 is 0.5, so 50% is 0.5. 7 divided by 100 is 0.07, so 7% is 0.07. The tool works to four decimal places and then trims any trailing zeros, so 50% shows as 0.5 rather than 0.5000, while a small or awkward percentage like 6.25% keeps its full 0.0625.

A worked example, step by step

Take 12.5%.

• Divide by 100: 12.5 ÷ 100.
• Slide the point two places left: 12.5 becomes 0.125.
• So 12.5% is 0.125.

The same move turns 3% into 0.03 and 250% into 2.5.

The form you actually calculate with

This conversion is the one you reach for most in real arithmetic, because you cannot multiply by a percent directly. To find 7% of a bill, you do not multiply by 7, you multiply by 0.07. To add 20% tax, you multiply by 1.20. Every one of those calculations quietly turns the percent into a decimal first. So this tool is really giving you the working form of a percentage, the number you feed into the actual sum.

The reverse trip: decimal to percent

This tool goes from a percent to a decimal. To go the other way, you multiply the decimal by 100, which slides the point two places right, and that is what the decimal to percent calculator does. Fraction, decimal, and percent are three ways of writing the same value, so each conversion is a step between two of them.

Questions people ask

Why divide by 100?

Because percent means by the hundred. A percentage counts hundredths, so dividing by 100 recovers the plain value it stands for.

Is there a shortcut?

Yes. Dividing by 100 is the same as sliding the decimal point two places to the left, so 45% becomes 0.45 without any long division.

How many decimal places does it show?

Up to four, with trailing zeros trimmed. So 50% reads as 0.5, while 6.25% keeps its full 0.0625.

What about a percentage over 100?

It still divides by 100, so 125% becomes 1.25, a decimal greater than 1.

How do I turn a decimal back into a percent?

Use the decimal to percent calculator, which multiplies by 100. It is the inverse of this tool.

References

On percent as a hundredth and its decimal value. Dividing a percentage by 100 undoes the per-hundred scaling and returns the plain decimal, which is the form used in ordinary calculation.

1. Eric W. Weisstein, "Percent," from MathWorld, a Wolfram resource, on percentages as ratios expressed per hundred.
2. Eric W. Weisstein, "Decimal Expansion," from MathWorld, a Wolfram resource, on representing a number in decimal places.