Grind your coffee blend coarse for cold brew, about the texture of kosher salt. Baratza’s grinder guidance for cold immersion brewing calls for setting burrs near the coarsest end of the adjustment scale, so particles look like coarse sea salt and produce fewer tiny dust particles called fines.
Cold water pulls flavor from coffee much slower than hot water does. Barista Hustle explains that cold extraction relies on diffusion over 12 to 24 hours, and a coarse grind prevents harsh, bitter flavors from being pulled out too fast.
Brew ratios are a weight measure, not a scoop count: most guides suggest 1:4 to 1:5 coffee to water for concentrate styles and 1:8 to 1:10 for ready-to-drink strength.
The Short Answer for Blends
A coarse grind still applies when your beans are a blend rather than a single origin. The blend itself does not change the target grind size much, because cold brew’s long steep time is the main thing your grind has to answer for.
What blend composition does change is the spread of particle sizes you should expect. Darker roasted beans are more brittle, so they shatter into more fines when ground.
To keep that in check, grind a touch coarser when your blend leans dark.
Use the table below to pick your starting grind
This table gives starting points based on steep time and brewer style. Treat these as a first attempt to dial in by taste, not fixed settings, since every grinder measures differently.
| Starting Grind | Feels Like | Typical Steep | Fits This Setup |
|---|---|---|---|
| Extra-coarse | Rock salt or peppercorns | 18 to 24 hours | Long immersion, Toddy-style systems, mesh filters |
| Coarse | Kosher salt or breadcrumbs | 12 to 16 hours | Standard immersion, French press jar |
| Medium-coarse | Rough sand | 8 to 10 hours at room temperature | Shorter steeps, slow-drip towers |
Barista Hustle places coarse cold brew particles in the range of roughly 1,000 to 1,400 microns. If you do not have a micron reference handy, the kosher salt texture check is the practical version of the same guidance.
Adjusting for Dark and Light Components in Your Blend
Darker roast components extract faster because brittle dark beans break down more easily, and they also generate more fines during grinding. That extra fine dust can over-extract during a long steep and push the cup toward bitterness.
If your blend contains light, dense beans like washed Ethiopian lots, those components resist extraction more. Grinding slightly closer to the medium-coarse end helps if the finished brew tastes thin or aggressively acidic.
Here is an important insight many cold brew guides miss: when a blended batch tastes inconsistent between batches, the problem often is not your recipe. It is that blends vary bean to bean, so keeping notes on each bag’s roast level matters more than chasing one perfect setting.
Grind the Beans Together, Right Before Brewing
Do not grind each component of the blend separately unless you know its exact role in the recipe. Grinding the blended beans together preserves the roaster’s intended balance, and many home brewers find this keeps flavor repeatable from batch to batch.
Grind right before brewing rather than days ahead. A burr grinder keeps particle size even, which is the whole game in immersion brewing.
Blade grinders are the weak link here. They smash beans unevenly, creating both boulders and dust that pull flavor at different rates.
A burr grinder like the Baratza Encore burr grinder, or the hand-cranked Timemore Chestnut C2 hand grinder, fits this job well. Key Specifications: conical steel burrs, stepped grind settings, and low retention for single-cup batches.
Freshness of the beans matters alongside the grind. If you are unsure how old is too old, our piece on blend freshness for cold brew covers it.
Troubleshooting by Taste
Your cup tells you which direction to adjust. Sour, watery, or thin cold brew can indicate too coarse a grind or too short a steep; go slightly finer next time or extend the steep by a few hours.
Bitter, chalky, or harsh results often point to a grind that is too fine, with excess fines doing damage over the long contact time. Grind slightly coarser next time.
Cloudy cups with heavy sludge usually mean fines are passing through your filter. Double filtration helps, meaning a metal mesh first followed by a paper or cloth filter, or simply grind coarser.
A difference worth noting: since cold brew steeps so much longer than hot methods, you get less forgiveness for fines than espresso. For hot brewing of the same style of blend, see our guide on grinding coffee blends for espresso.
If you’re still deciding which beans suit cold brewing at all, start with the best blend choices for cold brew.
Practical Starting Recipe
Weigh, do not scoop. A typical concentrate starting point is 250 grams of coarsely ground blend to about 1,000 grams of room-temperature water, then steep 12 to 16 hours at room temperature.
Refrigerated steeps run longer, roughly 18 to 24 hours, since colder water slows the process further. The Specialty Coffee Association’s brewing standards note that longer contact times call for reduced particle surface area to avoid pulling out too many bitter compounds, which is precisely why coarse wins here.
A small digital scale like the AmazonBasics digital kitchen scale makes gram-based ratios easy. SCA immersion brewing targets fall in the 18 to 22 percent extraction yield range, though grind size matters more than hitting an exact percentage at home.
Bottom Line
Grind your coffee blend coarse for cold brew, matching kosher salt in texture, roughly 1,000 to 1,400 microns according to Barista Hustle. Grind the blended beans together fresh, using a burr grinder, and start with 250 grams of coffee to about 1,000 grams of water.
Your next action: brew one small test batch, taste it, and adjust one notch finer or coarser next round.