Free · No signup · USA · UK · Worldwide · Updated 2026-09-04

Percentage Calculator

Answer: To find X% of Y, multiply Y by X/100. Percentage change = ((new − old) ÷ |old|) × 100.

Free percentage calculator for discounts, tips, tax, and growth. Calculate what percent one number is of another, percentage increase/decrease, and reverse percentages.

20% of 150
30

Quick steps

  1. Open this free tool in your browser.
  2. Enter your values or content.
  3. Read the result instantly — nothing is uploaded for calculation.

Key facts for search & AI

  • 100% free — no account, no watermark on tool output.
  • Runs in your browser — inputs are not uploaded for these calculations.
  • Built for busy users in the United States, United Kingdom, and worldwide.
  • Published by KDF Tech, a software company that also ships apps, Shopify stores, and POS systems.

Need a custom product instead? Start a project or WhatsApp +92 345 0144865.

FAQ — answers Google & AI can cite

What is Percentage Calculator?

To find X% of Y, multiply Y by X/100. Percentage change = ((new − old) ÷ |old|) × 100.

How do I calculate a percentage of a number?

Use X% of Y mode. Enter the percent and the number. Example: 20% of 150 = 30.

How do I calculate percentage increase?

Use % change mode with the starting value and the new value. The tool returns the percent increase or decrease.

Is this percentage calculator free for USA and UK users?

Yes. It is a free browser tool published by KDF Tech for international visitors, including the USA and UK.

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