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Percentage Calculator

Four calculation modes: what is X% of Y, X is what percent of Y, percentage change between two numbers, and X increased or decreased by Y percent.

What is X% of Y?
Quick percentages

Four calculation modes for any percentage problem. Results calculated instantly in your browser.

How to Calculate Percentages

Solve any percentage problem in four modes with The IT Hustle's free Percentage Calculator.

  1. 1
    Pick the mode that matches your questionChoose 'X% of Y' for portions, 'X is ?% of Y' for shares, '% Change' for growth or decline, or 'X + Y%' for increases and decreases.
  2. 2
    Enter your two numbersThe input labels update to match your chosen mode, so it's always clear which number goes where.
  3. 3
    Read the answer and the workingThe result appears instantly along with the formula used, so you can see how it was computed.
  4. 4
    Use the quick buttonsIn 'X% of Y' mode, one-tap buttons for common rates (5%, 10%, 15%, 20%, 25%, 50%) show tips, discounts, and splits instantly.
  5. 5
    Copy the resultClick Copy to grab the clean number for your spreadsheet or message.

Frequently Asked Questions

Subtract the old value from the new value, divide by the old value, and multiply by 100: ((new − old) ÷ old) × 100. Going from 80 to 100 is a +25% change. The % Change mode does this and displays the sign for you.

Because each percentage applies to a different base. 100 increased 50% is 150, but 150 decreased 50% is 75 — the decrease acted on the larger number. This asymmetry trips people up in pricing and investing constantly.

Use 'X% of Y' mode with the quick buttons — 15%, 20%, and 25% of your bill appear with one tap. Mental shortcut: 10% is just the decimal moved one place; double it for 20%.

Use the 'X is ?% of Y' mode: divide the part by the whole and multiply by 100. If 45 of your 180 site visitors clicked, that's 45 ÷ 180 × 100 = 25%.

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