Ratio Calculator — Simplify Ratios & Solve Proportions

Introduction Our free ratio calculator does two jobs in one place: it simplifies any ratio to its lowest terms and solves for a missing value in a proportion like a : b = c : d. Whether you are working through math homework, scaling a recipe, or comparing quantities at work, this tool gives you the exact answer with the working shown. No signup, no download — everything runs in your browser. How to Use 1. Choose a tab: "Simplify ratio" or "Solve proportion". 2. To simplify, enter two numbers separated by the colon (for example 12 : 18) and press Calculate. 3. To solve a proportion, fill in any three of the four boxes a : b = c : d and leave exactly one blank — the tool solves the missing value by cross-multiplication. 4. Read the result along with the step-by-step explanation. Press Reset to clear all fields. Key Features - Simplifies ratios to lowest terms using the greatest common divisor, with the steps shown. - Solves proportions with one unknown via cross-multiplication. - Handles decimals as well as whole numbers, with clear decimal equivalents. - Two modes in one clean interface — switch tabs without losing your work. - Fully private: all calculations run client-side in your browser; nothing is sent or stored anywhere. Why Choose Trencada Trencada's free online tools are built for speed and simplicity. This ratio calculator shows its working so you can trust — and learn from — every answer. No accounts, no tracking, no clutter: just fast, accurate math in seconds. Bookmark it for homework, cooking, crafts, and any everyday comparison task. FAQ Q: Is this ratio calculator really free? A: Yes — 100% free, with no signup and no limit on how often you use it. Q: Can it solve a proportion with a missing value? A: Yes. Leave exactly one of a, b, c, or d blank in the "Solve proportion" tab and the tool finds it by cross-multiplication. Q: Does it work with decimals? A: Yes — enter decimal values and the tool simplifies or solves them, showing decimal equivalents where helpful. Q: Is my input data stored anywhere? A: No. All calculations happen locally in your browser; nothing is uploaded or saved.