Ratio to Percentage Calculator

Convert any ratio A:B into percentage share values and proportions.

Overview

Converts part-to-part and part-to-whole ratios (A:B or A:B:C) into exact percentage shares and decimal fractions.

Formula & Calculation Method

Share A (%) = [A / (A + B)] × 100 | Share B (%) = [B / (A + B)] × 100

Calculates proportional ownership, profit sharing, and ingredient mixture percentages from ratio components.

Worked Example: Business Partnership Ratio of 3:2

Inputs: Ratio A = 3 | Ratio B = 2

  • Sum of ratio parts: 3 + 2 = 5 total parts
  • Partner A share = (3 / 5) × 100 = 60.0%
  • Partner B share = (2 / 5) × 100 = 40.0%

Summary: Ratio = 3:2 | Total Parts = 5 | Share A = 60.0% | Share B = 40.0%

Common Use Cases

  • Equity Ownership Splits: Calculate startup founder equity percentages from capitalization table share ratios.
  • Chemical & Concrete Mixing: Convert cement, sand, and aggregate ratios (e.g. 1:2:4) into batch mixture percentages.
  • Investment Asset Allocation: Convert portfolio equity-to-debt ratios (e.g. 70:30) into exact capital allocation percentages.

Frequently Asked Questions

What percentage is a 1:1 ratio?

50% each; there are 1 + 1 = 2 total parts, so each share is 1/2 = 50%.

What percentage is a 3:1 ratio?

75% and 25%; total parts = 4, so 3/4 = 75% and 1/4 = 25%.

How do I convert a 3-way ratio like 2:3:5 into percentages?

Sum the parts (2 + 3 + 5 = 10); then 2/10 = 20%, 3/10 = 30%, and 5/10 = 50%.

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