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Percent to Decimal Converter
To convert a percent to a decimal, divide by 100, which moves the decimal point two places to the left: 12.5% is 0.125, 7% is 0.07 and 0.5% is 0.005, not 0.5. Over 100% gives more than 1, so 150% is 1.5. This converter also gives the fraction, per mille and basis points.
Divide by 100.
- 12.5% means 12.5 per hundred, so divide by 100.
- Dividing by 100 moves the decimal point two places to the left: 12.5 becomes 0.125.
| Result | Value |
|---|---|
| Decimal | 0.125 |
| Fraction | 1/8 |
| Per mille | 125‰ |
| Basis points | 1,250 bp |
| Multiplier for a 12.5% increase | 1.125 |
| Multiplier for a 12.5% decrease | 0.875 |
The figure above is an example: put in your own, with or without the % sign. Whole numbers, decimals (0.5% or 0,5%), fractions of a percent (1/2%) and mixed numbers (33 1/3%) are all read. Worked out exactly in this browser and kept there; nothing is sent anywhere.
Type a percent, with or without the % sign, and read it as a decimal with the step that gets there. Small and fractional percents such as 0.5% and 33 1/3% are converted exactly.
A percent is a number of hundredths. Converting it to a decimal means writing the same value without the % sign, by dividing by 100: 45% is 45 hundredths, 0.45.
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- Nothing uploaded
- Shows every step
- Works offline
- Exact, no rounding errors
Key facts
| Detail | Answer |
|---|---|
| Rule | Divide by 100: move the decimal point two places left |
| Example | 12.5% = 0.125 = 1/8 |
| Small percents | 0.5% = 0.005; 1 basis point = 0.01% = 0.0001 |
| Over 100% | 150% = 1.5 |
| Accepts | 12.5, 12.5%, 0,5, 1/2, 33 1/3 |
| Where your numbers are kept | This browser only |
How to convert a percent to a decimal
One step, done the same way every time.
Write the percent without the sign
12.5% becomes 12.5.
Find the decimal point
A whole number such as 7 has it at the end: 7.
Move it two places to the left
Add zeros in front if you run out of digits: 7 becomes 0.07.
Check the size
Under 1% gives under 0.01; over 100% gives over 1.
Turn fractions of a percent into decimals first
1/2% is 0.5%, which is 0.005.
Who converts percents to decimals
Anyone who needs a percent in a formula, a spreadsheet or a calculator.
Spreadsheet users
The value a percent cell really holds.
Borrowers and savers
An interest rate ready to multiply.
Students
Percent to decimal, with the step written out.
Lab and clinic staff
A differential percent turned into a multiplier.
Finance readers
A move of 25 basis points as a decimal.
Programmers
A rate stored as a fraction of 1 rather than a percent.
Moving the point: 0.5% is 0.005, not 0.5
Converting a percent to a decimal is dividing by 100, which moves the decimal point two places left. The mistakes are almost all with percents below 1% or above 100%, where the answer looks wrong at a glance.
| Percent | Decimal | Common wrong answer | Why |
|---|---|---|---|
| 0.5% | 0.005 | 0.5 | Half of one percent; 0.5 would be 50% |
| 0.25% | 0.0025 | 0.25 | A quarter of one percent |
| 1% | 0.01 | 0.1 | 0.1 is 10% |
| 7% | 0.07 | 0.7 | The zero after the point is needed |
| 150% | 1.5 | 0.15 | Over 100% is over 1 |
| 1,000% | 10 | 0.1 | Ten times the whole |
The reason is in the definition: the percent sign is a number. The US National Institute of Standards and Technology’s style guide, Special Publication 811, section 7.10.2, states that the symbol % is used to represent the number 0.01, so 12.5% is 12.5 × 0.01 = 0.125. The same guide asks for a space between a number and the % sign in scientific writing (12.5 %), though everyday English, and this site, usually close it up.
Percent cells in Excel and Google Sheets
Spreadsheets store percentages as decimals, and most percentage errors in Excel and Google Sheets come from not knowing which one a cell holds. A cell showing 12.5% contains 0.125; multiply a price by it and you get 12.5% of the price. Type 12.5 into a formula instead and you get 12.5 times the price.
| What you do | What the cell shows | Why |
|---|---|---|
| Format an existing cell holding 10 as Percentage | 1000% | The value 10 is multiplied by 100 for display |
| Format an empty cell as Percentage, then type 10 | 10% | Excel reads numbers of 1 or more as percents |
| Format an empty cell as Percentage, then type 0.1 | 10% | Numbers below 1 are multiplied by 100 |
| Type 10% straight into a General cell | 10% (value 0.1) | The % sign converts as you type |
| =A1*12.5% with 80 in A1 | 10 | 12.5% is read as 0.125 |
Microsoft’s own help page, Format numbers as percentages in Excel, describes the first three rows: applying the Percentage format multiplies existing values by 100, so 10 shows as 1000%, while a number typed into an already formatted cell is treated differently depending on whether it is at least 1. The safe habit is to keep percentages as decimals in the cells and let the format add the % sign.
Basis points and per mille
Small percentages have their own units, and they are just more ways of moving the decimal point. Finance quotes interest rate moves in basis points, a hundredth of a percent; chemistry and some European languages use the per mille sign ‰, a tenth of a percent.
| Unit | As a percent | As a decimal | Seen in |
|---|---|---|---|
| 1 basis point (bp) | 0.01% | 0.0001 | A rate moving from 4.25% to 4.50% has risen 25 bp |
| 1 per mille (‰) | 0.1% | 0.001 | Blood alcohol limits, sea salinity (about 35‰) |
| 1 percent (%) | 1% | 0.01 | Per hundred |
| 1 part per million (ppm) | 0.0001% | 0.000001 | Trace concentrations |
The converter gives each percent in per mille and basis points too, and the two multipliers used to apply it: 12.5% more is × 1.125 and 12.5% less is × 0.875. Converting a percentage the other way, back from a decimal, is the decimal to percent converter; turning it into a fraction such as 1/8 is the percent to fraction calculator.
What this converter does not do
This converter changes how a number is written, not what it is. 12.5% and 0.125 are the same value. It does not apply the percent to anything; for 12.5% of a price use the percentage calculator. A fraction of a percent such as 1/3% has no finite decimal, 0.00(3), so the converter shows the repeating digits in brackets and a rounded value to the places you choose. A white cell differential reports each cell type as a percent, and the absolute neutrophil count guide shows the percent-to-decimal step used to turn it into a count.
This converter or an answer-only one
What this page does that a typical answer-only widget does not.
| This page | A typical calculator | |
|---|---|---|
| Fractions of a percent | 1/2% and 33 1/3% accepted | Decimals only |
| Repeating results | 0.(3) marked, and rounded | Rounded silently |
| Other forms | Fraction, per mille, basis points | The decimal only |
| Shows the step | Yes | Answer only |
| Exact arithmetic | No floating-point drift | Floating point |
| Your numbers leave the browser | Never | Varies |
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Frequently asked questions
How do you convert a percent to a decimal?
Divide by 100, which moves the decimal point two places to the left. 45% is 0.45, 12.5% is 0.125 and 3% is 0.03. If the percent is a whole number, the decimal point is after its last digit, so 7% is 7. moved two places: 0.07.
What is 0.5% as a decimal?
0.005. Half of one percent is half of 0.01. The common mistake is writing 0.5, which is 50%. Dividing any percent below 1% by 100 gives a decimal with at least two zeros after the point: 0.25% is 0.0025 and 0.1% is 0.001.
How do you write a percent over 100 as a decimal?
The same way: divide by 100. 150% is 1.5, 200% is 2 and 1,000% is 10. A decimal above 1 means more than the whole, so a 150% figure is one and a half times the original amount. The decimal point still moves two places to the left.
Why does Excel show 1000% when I format 10 as a percentage?
Excel stores percentages as decimals, so formatting a cell that holds 10 as Percentage multiplies it by 100 for display. Enter 0.1, or type 10% directly, to get 10%. Microsoft’s help page on formatting percentages describes this behaviour. The value in the cell stays 10 throughout.
How do you convert a fraction of a percent, like 1/4%, to a decimal?
Turn the fraction into a decimal first, then divide by 100. 1/4% is 0.25%, which is 0.0025. 33 1/3% is 33.(3)%, which is 0.(3), the decimal of one third. The converter accepts these as typed. Fractions of a percent are common in interest rates and fees, so the extra zeros matter.
What is a basis point as a decimal?
One basis point is 0.01%, which is 0.0001 as a decimal. A rate rising 25 basis points has gone up 0.25 percentage points. Per mille, written ‰, is a tenth of a percent, so 1‰ is 0.001. So 25 basis points is 0.0025 as a decimal.
Is 50% the same as 0.5?
Yes. 50% means 50 per hundred, and 50 ÷ 100 = 0.5. They are two ways of writing the same value. Multiplying by 0.5 and taking 50% give the same answer, which is why calculators and spreadsheets store percents as decimals.
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