Calzyra
CalzyraCALCULATE | CONVERT | SOLVE
FinanceInvestmentsHealthMathBlog
Calzyra
CalzyraCALCULATE | CONVERT | SOLVE

Smart calculators for every need. Trusted by millions of users worldwide for accurate, fast, and free calculation tools.

Popular Categories

  • Finance
  • Health & Fitness
  • Mathematics
  • Physics
  • Construction
  • Conversion

Finance Tools

  • Loan Calculators
  • Investment Calculators
  • Compound Interest
  • SIP Calculator
  • ROI Calculator
  • CAGR Calculator

Top Calculators

  • Mortgage Calculator
  • BMI Calculator
  • Percentage Calculator
  • Calorie Calculator
  • Tip Calculator

Company

  • About Us
  • Blog
  • Contact
  • Privacy Policy
  • Terms of Service

© 2026 Calzyra. All rights reserved.

Trusted by 2M+ monthly users
Home/Mathematics/Ratios & Proportions/Ratio Calculator
Math CalculatorRatios & Proportions

Ratio Calculator

Find a missing value in a proportion. Given three known values of a:b = c:d, solve for the unknown variable.

Updated 2025-01-153 min readCalzyra Math Team

Calculator

Enter your values below

CalculatorFree Tool

Enter the value of A.

Enter the value of B.

Enter the value of C.

Enter the value of D.

Select which value to solve for.

Formula & Methodology

How this calculator works

a / b = c / d

Uses the cross-multiplication property of proportions to solve for the missing value.

Frequently Asked Questions

Common questions about this calculator

Ratios & Proportions Calculators

Ratio Simplifier CalculatorRatio CalculatorProportion CalculatorUnit Rate CalculatorAspect Ratio CalculatorScale Factor CalculatorGolden Ratio CalculatorEquivalent Ratios CalculatorRatio to Fraction ConverterProportionality CalculatorMap Scale CalculatorDilution Calculator

Related Calculators

Ratio Simplifier Calculator

Simplify any ratio to its lowest terms.

Unit Rate Calculator

Calculate the rate per single unit.

Aspect Ratio Calculator

Calculate the aspect ratio of width to height.

Quick Links

All Math CalculatorsRatios & Proportions Category