Language
English English Vietnamese (Tiếng Việt) Vietnamese (Tiếng Việt) Chinese (简体中文) Chinese (简体中文) Portuguese (Brazil) (Português do Brasil) Portuguese (Brazil) (Português do Brasil) Spanish (Español) Spanish (Español) Indonesian (Bahasa Indonesia) Indonesian (Bahasa Indonesia)

Ratio & Proportion Calculator

Solve ratio and proportion problems instantly. Simplify ratios, find missing values in proportions, convert to fractions and percentages, or divide amounts by ratio.

What is Ratio & Proportion Calculator?

The Ratio & Proportion Calculator is a comprehensive tool designed to help you solve various ratio and proportion problems quickly and accurately. Whether you're a student learning math concepts, a professional working with data, or anyone who needs to work with ratios in daily life, this calculator provides all the essential functions you need.

Simplify Ratios

Reduce any ratio to its simplest form by finding the greatest common divisor (GCD)

Solve Proportions

Find missing values in proportion equations using cross multiplication

Convert Ratios

Transform ratios into fractions, decimals, and percentages

Divide by Ratio

Split any amount according to a given ratio with multiple parts

Why Use This Calculator?

Ratios and proportions are fundamental mathematical concepts used in countless real-world situations. This calculator eliminates manual calculations and potential errors, giving you instant, accurate results every time.

Cooking & Recipes

Scale ingredients proportionally for any serving size

Business & Finance

Calculate profit sharing, financial ratios, and data comparisons

Maps & Drawings

Work with scale drawings and map measurements

Science & Chemistry

Mix solutions and chemicals in precise proportions

Education

Learn and practice ratio and proportion concepts

Professional Use

Apply ratios in analytics, engineering, and project management

How to Use

The calculator is organized into four tabs, each serving a specific purpose. Select the tab that matches your calculation need.

Simplify Ratio

1

Enter First Number

Enter the first number (A) in the left input field

2

Enter Second Number

Enter the second number (B) in the right input field

3

View Results

The simplified ratio appears instantly below with the GCD (Greatest Common Divisor) in the details panel

Example: Enter 12 : 18 to get 2 : 3 (GCD = 6)

Proportion Solver

1

Enter Known Values

Enter three known values in the equation A : B = C : D

2

Leave One Empty

Leave one field empty (the value you want to find)

3

Get Solution

The missing value is calculated automatically and the solved field highlights in green

Example: Enter 2 : 4 = 3 : ? to find D = 6
Tip: If you fill all four values, the calculator verifies whether the proportion is valid.

Ratio Converter

1

Enter Ratio

Enter a ratio (A : B)

2

View Conversions

View the conversion results in multiple formats:

  • Fraction - A/(A+B) in lowest terms
  • Decimal - A divided by B
  • Percentage - Each part as a percentage of total
  • Parts - Description of parts out of total

Divide by Ratio

1

Enter Total Amount

Enter the total amount you want to divide

2

Set Ratio Parts

Enter the ratio parts (default is 3 parts). Use + and - buttons to add or remove parts (2-10 parts supported)

3

View Distribution

View each part's value and the total check sum

Example: Divide 100 by ratio 2:3:5 to get 20, 30, and 50

Quick Actions

Swap

Exchange the positions of A and B instantly

Clear

Reset all inputs and results to start fresh

Features

Ratio Simplifier

Reduce any ratio to its lowest terms instantly. The calculator finds the Greatest Common Divisor (GCD) of both numbers and divides accordingly.

Recipe Proportions

Simplify ingredient ratios for easier scaling

Math Problems

Reduce fractions in homework and exams

Equivalent Ratios

Find simplest form of any ratio relationship

Proportion Solver with Cross Multiplication

Solve proportion equations of the form A : B = C : D. The calculator uses the cross multiplication method (A × D = B × C) to find any missing value.

  • Solve for any of the four positions (A, B, C, or D)
  • Visual highlighting of the solved value
  • Step-by-step formula display
  • Proportion validation when all values are entered

Multi-Format Conversion

Convert any ratio into multiple formats simultaneously:

Fraction

Shows the first part as a fraction of the total

Decimal

Direct division result (A ÷ B)

Percentage

Both parts as percentages of the total

Parts Description

Natural language representation

Flexible Ratio Division

Divide any amount according to a ratio with comprehensive support:

  • Support for 2 to 10 ratio parts
  • Dynamic addition and removal of parts
  • Automatic total verification
  • Precise decimal calculations

User-Friendly Interface

Tab Navigation

Easy access to all functions through organized tabs

Real-Time Results

Calculations update instantly as you type

Quick Swap

Reverse ratios with a single click

Easy Reset

Clear button to start fresh anytime

Responsive Design

Works perfectly on all devices

Dark Mode

Eye-friendly interface for any lighting

Frequently Asked Questions

What is the difference between ratio and proportion?

A ratio compares two quantities (e.g., 2:3), while a proportion states that two ratios are equal (e.g., 2:3 = 4:6). Ratios show relationship between numbers; proportions show equivalence between two ratios.

How does the proportion solver work?

The calculator uses cross multiplication. For A : B = C : D, the rule is A × D = B × C. When you leave one value empty, the calculator solves for that unknown using this formula.

Formula: If solving for D, then D = (B × C) ÷ A

What is GCD and why is it shown?

GCD (Greatest Common Divisor) is the largest number that divides both parts of a ratio evenly. It shows how much the ratio was reduced. For example, 12:18 has GCD = 6, so both are divided by 6 to get 2:3.

Can I use decimal numbers?

Yes, the calculator accepts decimal numbers in all fields. Results are displayed with appropriate precision to ensure accuracy.

What happens if I enter zero?

The calculator handles zero values appropriately. A ratio like 0:5 simplifies to 0:1. Division by zero is prevented and will show no result to avoid mathematical errors.

How many parts can I divide by?

The Divide by Ratio feature supports 2 to 10 parts. Use the + and - buttons to add or remove parts as needed for your calculation.

Is my data saved?

No, all calculations are performed in your browser. Your input is not stored or sent to any server, ensuring complete privacy.

Privacy: 100% client-side processing - your data never leaves your device

Can I use this on mobile devices?

Yes, the calculator is fully responsive and works on smartphones, tablets, and desktop computers. On smaller screens, tab labels are hidden to save space, showing only icons for a cleaner interface.

Simplify Ratio

:
-

Proportion Solver

Leave one field empty to solve
:
=
:
-

Ratio Converter

:
Fraction -
Decimal -
Percentage -
Parts -

Divide by Ratio

: :
Enter two numbers to simplify a ratio to its lowest terms
Leave one field empty in Proportion Solver to find the missing value
Use Swap button to quickly reverse ratio positions
All calculations are done in your browser
Want to learn more? Read documentation →
1/5
Start typing to search...
Searching...
No results found
Try searching with different keywords