Does the calculator handle successive percentages?

Yes. Successive percentages are multiplied, not added: −20% then −10% = ×0.80 × 0.90 = ×0.72, i.e. −28% (not −30%).

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Percentage Calculator

How much is 20% of 150? Calculate a discount, a salary increase, a margin, a grade out of 20 or VAT? This percentage calculator answers instantly: the 4 essential operations (percentage of a number, percentage between two numbers, inverse, add/subtract), plus increase and decrease, variation, percentage difference, original value found, remainder, goals, successive percentages and fraction ⇄ decimal ⇄ percentage conversions. Each result comes with its formula and calculation steps, with percentage points and compound calculations. Free, no account and 100% in your browser.

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8 specialized modes0 data sent to the server∞ steps & local history

The tool

Your online percentage calculator

Pick a mode, type a value: the result, formula, steps and summary sentence update as you type. Both comma and dot are accepted.

Percentage Calculator

Online Productivity, Office & Documents

Decimales

01 How much is X% of Y?

% of

Result—

Show calculation

02 X is what percentage of Y?

is ? % of

Result—

Show calculation

03 X is Y% of which number?

% of ?

Result—

Show calculation

04 Add or subtract X% from Y

Result—

Show calculation

9 Successive percentages (cumulative)

Starting value

Examples:

Final value—

Total variation—

Global coefficient—

Show detail by step

Step	Value	Variation	After	% cumulative

Reminder: successive percentages multiply, they do not add up. −20% then −10% = ×0.8 ×0.9 = ×0.72, i.e. −28% (not −30%). An increase of 5% per month for 12 months is ×1.05¹² ≈ +79.6% for the year.

Local calculation history

Features

All percentage calculations, in one place

From everyday calculations (discounts, sales, VAT, grades) to professional uses (margins, goals, trends), one engine answers all percentage questions.

Formulas, steps and sentences

Each result displays its exact formula, step-by-step detail and a summary sentence ("20% of 150 = 30"). Ideal for understanding, checking homework or explaining a calculation.

Do a calculation

Inverse and compound calculations

Find the original value before an increase or discount, determine a total from a share, follow successive or cumulative percentages: the engine handles both the front and back of the calculation.

Try the inverse

Total precision, 100% private

Exact results and configurable rounding, comma or dot, large and small numbers: nothing is sent to the server. History, steps and your inputs stay on your device.

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How it works

Calculate a percentage in three steps

No installation, no sign-up: a calculator that is always ready, wherever you are.

Enter

Type your numbers (e.g. 20 then 150), accepting the comma "20.5" as well as the dot. Choose the calculation type: the four essentials are already there, before your eyes.

Get the result

The result appears instantly, with its formula, calculation steps and a written summary sentence. Adjust the number of decimals if needed.

Reuse

Copy the result with one click, resume a calculation from history, share the link with pre-filled values or print the complete sheet of your calculations.

Quick reference

Percentage calculation examples

Some frequently asked questions and their answers — all these operations are available in the tool.

Question	Calculation	Result
20% of 150	150 × 20 ÷ 100	30
30 is what % of 120?	30 ÷ 120 × 100	25%
30 is 25% of which number?	30 × 100 ÷ 25	120
+20% on 150	150 × 1.20	180
−20% on 150 (discount)	150 × 0.80	120
From 100 to 120, variation?	(120 − 100) ÷ 100 × 100	+20%
Price €120 after +20%: before?	120 ÷ 1.20	€100
18 out of 20, as a grade	18 ÷ 20 × 100	90%
15% of 30%	0.15 × 0.30	4.5%
From 2% to 3%, in percentage points	3 − 2	+1 pp
20% VAT included on €120 incl.	120 ÷ 1.20	€100 excl.
−20% then −10%	× 0,80 × 0,90	−28 %

Trust

Exact calculations, private values

The calculation engine is written in JavaScript and embedded directly in the page: it works even offline, without an account and without a server.

Exact results

Verified formulas, configurable rounding, French display (comma and spaces): "1,234.50" instead of "1234.5".

Pedagogical method

Each result is broken down: fraction (25/100), operation (0.25 × 150), coefficient (×1.20) then summary. Perfect for learning and checking.

100% local

No data leaves your device, not the history, not the steps, not the input values. Your salary, margin or budget calculations stay private.

FAQ

Frequently asked questions about percentages

The most commonly asked questions — and their simple answers.

How do you calculate a percentage of a number?

To calculate X% of Y, multiply Y by X then divide by 100: 20% of 150 = 150 × 20 ÷ 100 = 30. The Volade calculator applies this formula instantly and displays the fraction (20/100) then the operation (0.20 × 150).

How do you know what percentage one number represents compared to another?

Divide the part by the total then multiply by 100: 30 out of 120 = 30 ÷ 120 × 100 = 25%. We also write "30 is 25% of 120". The "X is what % of Y" mode does the calculation and writes the sentence.

How do you calculate a discount or a percentage reduction?

A discount of X% on a price Y is calculated with the coefficient: final price = Y × (1 − X/100). Example: −20% on 150 = 150 × 0.80 = 120. The "Subtract X%" mode gives you the final price and the exact coefficient.

How do you find the original price before an increase or a discount?

Divide the final value by the applied coefficient: after a 20% increase, the price of 120 came from 120 ÷ 1.20 = 100. After a 20% discount, it came from 120 ÷ 0.80 = 150. The "Original value" mode avoids the classic mistake of subtracting 20% from the current price.

How do you calculate a percentage increase (salary, price)?

Compare the final value to the initial value: increase = (final value − initial value) ÷ initial value × 100. An increase from 100 to 120 = +20%, and the multiplication coefficient is 1.20.

What is the difference between variation in % and percentage points?

A rate that goes from 2% to 3% increases by 1 percentage point (the arithmetic difference), but by 50% in relative variation (1 ÷ 2 × 100). Both concepts are displayed in the "Points & ratios" mode with an explanatory sentence.

A free percentage calculator, in your browser

Discounts, sales, VAT, salaries, margins, grades and goals: do all your calculations in an instant, without an account, without sending data. Go premium to unlock the entire Volade ecosystem.

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Percentage Calculator

Your online percentage calculator

Percentage Calculator

01 How much is X% of Y?

02 X is what percentage of Y?

03 X is Y% of which number?

04 Add or subtract X% from Y

5 Increase or decrease between two values

a Why doesn't +25% then −25% return to the starting point?

6 Difference between two numbers

7 Find the original value

8 Remainder, goal, share of a total

9 Successive percentages (cumulative)

10 Conversions percentage ⇄ decimal ⇄ fraction

11 Percentage points

12 Percentage of a percentage

All percentage calculations, in one place

Formulas, steps and sentences

Inverse and compound calculations

Total precision, 100% private

Calculate a percentage in three steps

Enter

Get the result

Reuse

Percentage calculation examples

Exact calculations, private values

Exact results

Pedagogical method

100% local

Frequently asked questions about percentages

A free percentage calculator, in your browser