---
type: "tool"
title: "Percentage Calculator"
description: "Free percentage calculator with 8 modes. Calculate percentages, increase or decrease, reverse percentages, differences, discounts and marks with formulas and worked steps."
resource: "https://www.gstcalculators.in/percentage-calculator.html"
language: "en"
bundle_generated: "2026-10-08"
---

# Percentage Calculator

Free percentage calculator with 8 modes. Calculate percentages, increase or decrease, reverse percentages, differences, discounts and marks with formulas and worked steps.

- Canonical page: [Percentage Calculator](https://www.gstcalculators.in/percentage-calculator.html)
- Publisher: [Tools Master Hub / GSTCalculators.in](../site.md)
- Category: [Basic Financial Calculators](../categories/basic.md)

This is a discovery summary of the public page, not an independently reviewed replacement. Use the canonical page for current inputs, assumptions, formulas, source links and results. The bundle generation date does not mean that tax rules were reviewed on that date.

## Topics on the page

- Percentage of a number
- How to use this calculator

## Questions and answers from the visible page

### How do I calculate a percentage?

Divide the part by the whole and multiply by 100. For example, 30 out of 150 is 20%. To find 20% of 500, multiply 500 by 20 and divide by 100: the answer is 100.

### How are percentage change and percentage difference different?

Percentage change uses the original value as the baseline. Percentage difference uses the average of two values. From 80 to 100 is a 25% increase, but their percentage difference is about 22.22%. Change requires a positive original value; difference accepts nonnegative values, except two zeroes.

### Can I add two successive discounts together?

No. Each discount applies to the remaining price. A 20% discount followed by 10% gives a total discount of 28%, not 30%. Leave the second discount blank for a single discount.

### How do I recover the value before a percentage change?

Divide the final value by 1 plus the increase rate, or 1 minus the decrease rate, written as a decimal. After a 20% decrease, a final value of 800 gives 800 ÷ 0.8 = 1,000. A 100% decrease cannot be reversed uniquely.

## Formulas and worked examples

See the [eight-mode percentage reference](../guides/percentage-calculations.md).

## Accuracy and corrections

[Methodology](https://www.gstcalculators.in/methodology.html) · [Editorial policy](https://www.gstcalculators.in/editorial-policy.html) · [Disclaimer](https://www.gstcalculators.in/disclaimer.html) · [Report a problem](https://www.gstcalculators.in/contact.html).