Percentage Calculator
Four calculations on one page: a percentage of a number, what percentage one number is of another, the percentage change between two values, and adding or subtracting a percentage. Pick the question, type the numbers, and the answer appears with the working shown underneath.
Instant results — nothing is uploaded
What is X% of Y?
What is % of ?
Fill both boxes to see the answer.
X is what percent of Y?
is what percent of ?
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Percentage increase or decrease
From to is what percent change?
Fill both boxes to see the answer.
Add or subtract a percentage
% to
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How to Use
- Choose the question you are trying to answer from the dropdown.
- The two input labels change to match — type your numbers into them.
- The answer appears immediately, with a plain-English explanation below it.
- Use Clear to reset both fields.
Features
- Three calculation modes — percentage of a number, one number as a percentage of another, and percentage change.
- Working shown — each answer comes with a sentence explaining how it was reached, so you can sanity-check it.
- Increase or decrease detected — percentage change tells you which direction the move was, not just the size.
- Handles decimals and negatives — useful for temperature changes, losses, and rates that are not whole numbers.
- Clear error messages — dividing by zero is caught and explained rather than showing something meaningless.
- No rounding surprises — results are kept to four decimal places instead of being rounded to whole numbers.
Percentage Formulas
| What you want | Formula | Example |
|---|---|---|
| X% of Y | (X ÷ 100) × Y | 15% of 200 = 30 |
| X as a % of Y | (X ÷ Y) × 100 | 30 of 150 = 20% |
| Percentage change | ((New − Old) ÷ Old) × 100 | 200 → 250 = +25% |
| Add X% to a number | Y + (Y × X ÷ 100) | 2000 + 15% = 2300 |
| Subtract X% from a number | Y − (Y × X ÷ 100) | 2000 − 15% = 1700 |
| Find the original before a % | Result ÷ (1 + X ÷ 100) | 2300 after +15% = 2000 |
Worked Examples
Exam marks. You scored 693 out of 1100. Use the second calculator: 693 ÷ 1100 × 100 = 63%.
Salary increment. Your salary is Rs. 85,000 and you are offered a 12% raise. Use the fourth calculator with Add: 85,000 + 12% = Rs. 95,200, so the raise itself is Rs. 10,200.
Price change. A item cost Rs. 450 last year and Rs. 520 now. The third calculator gives +15.56%, which is the inflation you actually felt.
Tip or commission. A freelance platform takes 10% of a $500 payment. The first calculator gives 10% of 500 = $50, leaving $450.
Frequently Asked Questions
How do I work out a percentage of a number?
Choose the first mode, put the percentage in the left box and the number in the right box. For example, 20% of 500 is 100. The formula is (percentage ÷ 100) × number.
How is percentage change calculated?
It is the difference between the two values divided by the original value, expressed as a percentage: ((new − original) ÷ original) × 100. Going from 80 to 100 is a 25% increase; going from 100 to 80 is a 20% decrease. The two are not the same, which surprises a lot of people.
Why does a 50% drop need a 100% rise to recover?
Because the base changes. If 200 falls by 50% it becomes 100 — and to get from 100 back to 200 you need to add 100, which is 100% of the new base. This matters when reading anything about prices, rates or traffic figures.
Can I use negative numbers?
Yes. Percentage change uses the absolute value of the original number as the base, so it still works correctly when the starting value is negative.
Is anything saved or sent anywhere?
No. The calculation runs in your browser and the numbers are never uploaded, stored or logged.
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Percentages come up constantly when you are working out what a payment is actually worth — our guide to the real cost of receiving freelance payments in Pakistan traces every fee on a $500 payment.