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Cold Brew
Calculator
We built this to stop doing cold brew math on napkins. Now you don't have to either — plan your batch, dial in dilution by TDS, and portion concentrate into any container in seconds.
Use The Calculator →Three tools. One workflow.
Brew Planner
Tell it how many servings you need. It tells you exactly how much coffee to grind, how much water to brew with, and how much water to add after — no math required.
Dilution
Measure your concentrate's TDS after brewing and enter it here. The calculator figures out exactly how much water to add to bring it to your target ready-to-drink strength.
Partial Batch
Filling a growler, keg, or jug? Enter the container size and your concentrate TDS. Get the exact concentrate-to-water split and a serving count for that container.
How It Works
We run a cold brew program at Coffee Break and kept running into the same problem: brewing concentrate is straightforward, but the dilution math to get from concentrated cold brew to a ready-to-drink product — accounting for ice, cream, serving size, and yield — is tedious to do by hand. We built these three tools to solve exactly that. Each one handles a different stage of the process.
Brew Planner
Start here when planning a new batch. Enter how many servings you need and choose your cup size. The calculator returns exact amounts for coffee, brew water, and dilution water.
Dilution
Use this after brewing once you've measured your concentrate's TDS. Enter the volume and TDS reading, and the calculator tells you exactly how much water to add to hit your target RTD strength.
Partial Batch
Filling a specific container — growler, keg, or jug? Enter the container size and your concentrate's TDS. The calculator splits the fill between concentrate and water and shows how many servings it yields.
Tips for Accurate Results
- Adjust your brew ratio, TDS targets, and other defaults in the Settings tab to match your equipment and taste profile.
- Use an optical refractometer to measure TDS after brewing — this unlocks the Dilution tab for precise water additions.
- Weigh your coffee rather than scooping. Even a 1–2% variance in coffee weight compounds across large batches.
- Cold brew typically steeps 12–24 hours at room temperature. We grind at the coarsest setting (20 on our Mahlkonig Guatemala), and brew for 16–20 hours.
Recommended Products
Coffee and equipment for a consistent cold brew program.
Wholesale Coffee Partner Program
We can set you up with a great coffee suited for cold brew, espresso, batch brew, or whatever your purpose. Roasted to order in Huntsville, AL.
Apply to become a partner → EquipmentAlto Cold Brew
Great filters that don't rip, plus a well-designed bucket system with a drain basket that makes extraction and cleanup much cleaner.
Shop Alto Cold Brew → WaterThird Wave Water — Cold Brew Profile
We start with RO water and remineralize using their Cold Brew Profile. The right mineral balance makes a noticeable difference in extraction and flavor clarity.
Shop Third Wave Water → EquipmentOptical Refractometer
There are a lot of models out there — some pair with an app for tracking brew parameters. We use this affordable option from Amazon. Understanding TDS% is essential for the Dilution and Partial Batch calculators.
View on Amazon →