Everyday Percentage Calculator
92 QuickCalc — percentages, discounts, tax, and margins, explained simply.
Calculate percentages, discounts, increases, tax and profit margins without memorising formulas. Choose what you want to calculate, enter your numbers, and get an instant explanation.
Real-life examples, worked out
Salary increase
Your salary changed from 100,000 to 120,000. That's a 20% increase.
Payment progress
You paid 25,000 from a total of 100,000. You've paid 25%.
Shopping discount
A 20% discount on 5,000 saves you 1,000. You pay 4,000.
Included tax
If the total is 118,000 including 18% tax, the original amount is 100,000 and the included tax is 18,000.
Business profit
If an item costs 8,000 and sells for 10,000, the profit is 2,000, the margin is 20%, and the markup is 25%.
How to calculate a percentage
To find a percentage of an amount, multiply the amount by the percentage and divide by 100: amount × percentage ÷ 100. So 15% of 80,000 is 80,000 × 15 ÷ 100 = 12,000.
To find what percentage one number is of another, divide the smaller (or partial) amount by the total and multiply by 100: part ÷ total × 100. Paying 25,000 out of 100,000 is 25,000 ÷ 100,000 × 100 = 25%.
How to calculate percentage increase or decrease
Percentage change compares a new value to an old one: (new − old) ÷ old × 100. A salary moving from 100,000 to 120,000 is a 20% increase; a price dropping from 5,000 to 4,000 is a 20% decrease. The sign of the result tells you the direction — positive is an increase, negative is a decrease, and zero means no change.
This only works when the old value isn't zero — there's no percentage change from nothing, so the calculator flags that case instead of dividing by zero.
How to calculate a discount
A discount removes a percentage of the original price. First find the savings — original price × discount ÷ 100 — then subtract that from the original price to get the final price. A 20% discount on 5,000 saves 1,000, bringing the price down to 4,000.
To work backwards from a sale price to the original price, divide by (1 minus the discount as a decimal) instead of adding the percentage back on: original = final ÷ (1 − discount ÷ 100). An 8,000 price tag after a 20% discount started at 8,000 ÷ 0.80 = 10,000.
How to remove included tax
A common mistake is subtracting the tax percentage straight from a tax-inclusive total — that overcorrects, because the tax rate was applied to the smaller original amount, not to the total itself. The correct approach divides the total by (1 + the tax rate as a decimal): original = inclusive amount ÷ (1 + rate ÷ 100).
A total of 118,000 including 18% tax has an original amount of 118,000 ÷ 1.18 = 100,000, and the included tax is the difference: 18,000. Subtracting 18% from 118,000 directly would (incorrectly) give 96,760.
Profit margin vs. markup
Margin and markup both start from the same profit — selling price − cost price — but divide it by different numbers. Margin divides by the selling price (profit ÷ selling price × 100) and shows what share of each sale is profit. Markup divides by the cost price (profit ÷ cost price × 100) and shows how much was added on top of what it cost you.
An item bought for 8,000 and sold for 10,000 has a 2,000 profit, a 20% margin, and a 25% markup — two different numbers describing the same sale. Mixing them up is a common source of underpricing, since a target margin always needs a higher markup percentage to reach it.
More finance tools
If you're tracking where your money goes each month, the Expense Calculator breaks down spending against income. Once you've worked out a discount, tax amount, or margin here, the Invoice & Quotation Generator turns those numbers into a professional PDF for a client. And if you're pricing out a new project rather than a sale, the Website & Mobile App Cost Calculator gives you a realistic budget range in seconds.
Common questions
How do I calculate a percentage of an amount?+
Multiply the amount by the percentage and divide by 100. For example, 15% of 80,000 is 80,000 × 15 ÷ 100 = 12,000. Use the "Find a percentage" calculator above to do this instantly.
How do I find what percentage one number is of another?+
Divide the part by the total and multiply by 100. For example, if you paid 25,000 out of a 100,000 total, that's 25,000 ÷ 100,000 × 100 = 25%.
How do I calculate a percentage increase?+
Subtract the old value from the new value, divide by the old value, and multiply by 100. Going from 100,000 to 120,000 is (120,000 − 100,000) ÷ 100,000 × 100 = 20% increase. The same formula gives a negative result for a decrease.
How do I calculate the original price before a discount?+
Divide the final price by (1 minus the discount as a decimal). If an item costs 8,000 after a 20% discount, the original price was 8,000 ÷ (1 − 0.20) = 10,000.
How do I remove tax from a tax-inclusive total?+
Don't subtract the tax percentage directly — divide the total by (1 + the tax rate as a decimal) instead. A total of 118,000 including 18% tax is 118,000 ÷ 1.18 = 100,000 original, with 18,000 as the included tax.
What is the difference between profit margin and markup?+
Both start from the same profit figure but divide it differently. Margin is profit ÷ selling price, showing how much of each sale is profit. Markup is profit ÷ cost price, showing how much you added on top of cost. They're only equal when profit is zero.
Are my calculations stored or uploaded?+
No. Every calculation runs locally in your browser using plain JavaScript — nothing you type is uploaded, saved, or sent to a server.
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