# Percentage Calculator

Solve common percentage questions including percentage of a total, value from a percentage, and percentage change

> Canonical page: https://elysiatools.com/en/tools/math-percentage-calculator

- **Category:** Math & Numbers

- **Keywords:** percentage, percent, ratio, calculator, percentage change

## Overview

The Percentage Calculator is a versatile mathematical tool designed to solve common percentage-based problems with precision. It allows users to quickly determine the percentage of a total, calculate a specific value from a given percentage, or find the percentage change between two numbers, all while offering customizable decimal precision for accurate reporting.

## Inputs

- **Mode** (select)
- **Value** (text): e.g. 45
- **Total** (text): e.g. 120
- **Percentage** (text): e.g. 15
- **Original Value** (text): e.g. 80
- **New Value** (text): e.g. 96
- **Decimal Places** (number)

## When to use

- Calculating the percentage of a specific value relative to a total sum for financial or statistical reports.
- Determining a numerical value when only the percentage and the total amount are known.
- Measuring the percentage increase or decrease between original and new values to track growth or loss.

## How it works

- Select the desired calculation mode: Value as % of total, Value from X%, or % change.
- Input the required numerical data into the corresponding fields such as Value, Total, or Original/New values.
- Set the preferred number of decimal places, ranging from 0 to 12, to control the output precision.
- The tool processes the inputs and returns the calculated percentage or value in a structured JSON format.

## Use cases

- Business analysts calculating market share by comparing individual company revenue to total industry sales.
- Retailers determining the percentage discount applied to products during seasonal sales events.
- Students and educators solving mathematical problems involving ratios, proportions, and percentage changes.

## Frequently asked questions

### How do I calculate a percentage increase?

Select the '% change from original to new' mode and enter your starting and ending values.

### Can I adjust the precision of the result?

Yes, you can specify the number of decimal places from 0 up to 12 in the settings.

### What is the 'Value as % of total' mode used for?

It calculates what percentage a specific number represents out of a larger total amount.

### Can I find a number if I only know its percentage of a total?

Yes, use the 'What value is X% of total' mode to find the specific numerical amount.

### Is this tool suitable for calculating sales tax?

Yes, it can be used to find the tax amount by calculating a percentage of the total price.

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