DIY Cost Tools
Cold Brew Ratio Calculator
Calculate coffee grounds from water mass and a chosen water-to-coffee ratio for cold-brew preparation.
How to use this calculator
- Replace every example value with your own measurements, label values or planning assumptions.
- Keep each value in the unit printed beside its field.
- Select Calculate, then compare the result with the formula and limitations below.
Formula and method
Coffee grams = water grams × coffee parts ÷ water parts. Water fluid ounces approximate water grams ÷ 29.5735. Total brew mass = (water + coffee) ÷ 1,000.
Results are hidden whenever an input changes or validation fails, so an older answer cannot be mistaken for the current calculation.
Worked example
Water mass = 1000 g; Water parts = 8 parts; Coffee parts = 1 parts. The calculator returns Coffee grounds = 125 g; Water volume = 33.8 US fl oz; Total brew mass = 1.13 kg.
The worked example uses the same default values displayed in the calculator.
Limitations and safety
Frequently asked questions
What should I enter first?
Start with measurements or rates from the project, product label, service quote or equipment specification. Replace every example value before relying on the estimate.
Why can the real result differ?
Taste, grind, roast, extraction time and retained water affect strength and finished yield. Prepare with clean equipment, refrigerate promptly and follow food-safety guidance.
Does the calculator round purchases up?
Only outputs labeled as whole packages, vents, heaters, pails or similar counts are rounded up. Keep extra precision for planning and follow supplier packaging.
Review notes and reference
Reviewed October 5, 2026. The formula was independently checked against the displayed default example, and the calculator was tested for valid defaults, empty input, invalid formats, range boundaries and recovery. Reference: USDA Food Safety Basics. Explanations and examples are original.