Calculator Tools

Percentage Calculator

Three calculators in one: find what percentage one number is of another, calculate a percentage of a value, or find the percentage change between two numbers. All with instant step-by-step results.

Step-by-step results shown No sign-up required Browser-only, no upload
What is % of ?
is what % of ?
From to

Runs entirely in your browser — no data is sent to a server

Input Text Output Text Browser-only No upload by default

Features

  • Mode 1: What is X% of Y? (e.g. 15% of 200 = 30)
  • Mode 2: X is what % of Y? (e.g. 45 is what % of 180?)
  • Mode 3: Percentage increase/decrease from A to B
  • Step-by-step formula shown for each mode
  • Inverse calculation (reverse mode)
  • Works with decimals and negative numbers
  • No account, browser-only

How to use it

  1. Select the calculation mode that matches your question.
  2. Enter the values in the input fields.
  3. The result and formula appear instantly.
  4. Switch modes to approach the problem differently.

Use cases

  • Calculating tips and discounts while shopping
  • Finding percentage change in sales or metrics
  • Tax calculations (VAT, income tax)
  • Grade calculations (marks scored out of total)

Limitations

  • Browser processing depends on available device memory for very large inputs.
  • Tool-specific limits based on file format or browser support are noted on each tool page.
See also

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Questions & answers

Frequently asked

What is 20% of 150?

20% of 150 = 0.20 × 150 = 30. Type 20 in the percentage field and 150 in the value field in Mode 1.

How do I calculate a percentage increase?

Use Mode 3. Enter the original value and the new value. The percentage increase is ((new − old) ÷ old) × 100.

Does Percentage Calculator upload my content?

Your file or text is processed in your browser and is not uploaded.

Is Percentage Calculator free to use?

Yes. All OnlineTextLab tools are free with no account required.