How do I work out a percentage of a number?

Multiply by the percentage and divide by 100. 15% of 240 is 240 × 15 ÷ 100 = 36.

How do I find what percentage one number is of another?

Divide the part by the whole and multiply by 100. 36 out of 240 is 36 ÷ 240 × 100 = 15%.

What is the difference between percent and percentage point?

A move from 4% to 6% is two percentage points, and also a 50% increase. Use percentage points when the thing changing is itself a percentage.

Why does a discount then a tax not cancel out?

Same reason a rise and fall do not: each is applied to a different base. The order also matters when the rates differ, which is worth checking on an invoice.

Percentage Calculator

Handles the percentage questions that come up in practice — a share of a total, an increase or decrease, and what a change was as a percentage.

Runs in your browser — nothing is uploaded

Your numbers

Value (X)

Total (W)

Percentage (P)%

Every form of the question, answered at once

Fill in what you know — the answer you need is one of these three.

What is 14% of 250?

35250 × 14 ÷ 100

35 is what percent of 250?

14%35 ÷ 250 × 100

35 is 14% of what?

25035 ÷ 14 × 100

Need this as an API?

Why use it

Built to be genuinely useful

The three real questions

What is X% of Y, X is what percent of Y, and what is the change from X to Y — rather than one box that only answers the easiest of the three.

Increase and decrease are separate

Because they are not symmetric, and treating them as though they were is the most common percentage error there is.

Nothing is uploaded

The arithmetic runs in your browser. Salary, marks and tax figures are nobody else's business, and none of it is sent anywhere.

Free, no sign-up

No account, no limit on how many times you run it, and no result held back.

How it works

Three steps

1
Pick the kind of question.
2
Enter the numbers.
3
Read the answer and the working.

Why a 20% fall does not undo a 20% rise

A percentage is always of something, and the something changes. A ₹1,000 item raised by 20% is ₹1,200; reduced by 20% from there it is ₹960, not ₹1,000 — because the second 20% was taken from the larger figure.

This is behind a great deal of misleading advertising and a good deal of honest confusion. A salary cut of 10% followed by a rise of 10% leaves you below where you started. Reversing a 20% increase requires a decrease of about 16.7%, and the general rule is that the two never match.

Percent versus percentage point

If an interest rate moves from 4% to 6%, that is a rise of two percentage points and a rise of fifty percent. Both are true, they describe the same change, and they sound wildly different — which is exactly why the wrong one gets quoted.

The convention worth keeping is to use percentage points whenever the quantity is itself a percentage, and percent for everything else. It removes the ambiguity, and noticing which one a report uses is a quick way to tell whether it is trying to inform you or impress you.

FAQ

Questions people ask

API access

Need Percentage Calculation in Your App?

Add percentage calculation to your learning platform, app or internal tooling through API access.

Tell us what you are building, how you plan to use it and the volume you expect. We will come back to you with availability, integration details and a quote for your usage.

Related tools

More student tools

Available tools are linked; the rest are in development.

GPA Calculator CGPA Calculator Grade Calculator Attendance Calculator Study Time Calculator AI Writer AI Summarizer AI Paraphraser AI Humanizer AI Grammar Checker AI Rewriter AI Translator

All Student Tools

Need a tool like this for your business?

We build internal tools, dashboards and automation that fit how your team works.

See Our Services