How to Choose a Coffee Grinder

If you change one thing about your coffee setup this year, change the grinder. Not the machine. Not the beans. The grinder.

Here's the reason, and it isn't a purist's argument: every brew method is a recipe for extracting flavour at a particular particle size. Espresso wants roughly 200–300 microns. Pour-over sits around 400–700. French press is coarser still. Get the particle size wrong by 20 microns and a sweet shot turns bitter, or sour, and no amount of technique rescues it.

A $300 espresso machine fed by a $50 blade grinder makes worse coffee than a $90 hand grinder and a $30 dripper. We've tested this the boring way — same beans, same water, same dose, swapping only the grinder — and the gap is larger than any upgrade you can make further down the line.

Below are the five specs that change what lands in your cup, the three that don't, and a table you can use to decide in about a minute.

1. Burr, not blade. This one isn't negotiable.

A blade grinder is a propeller in a cup. It shatters beans at random, so a single dose contains everything from powder to gravel. That's why blade-ground coffee tastes simultaneously bitter and sour: you extracted the dust too far and the boulders not at all.

A burr grinder pushes beans between two cutting surfaces set a fixed distance apart. Every particle passes the same gap, so the output is a narrow range rather than a random spread.

2. Conical or flat? Less dramatic than the forums suggest.

Both are burrs. The difference is shape and, at the margins, flavour.

Conical burrs (a cone inside a ring) cut more slowly, run cooler, and produce a slightly wider particle spread. That wider spread tends to read as body and forgiveness — a conical grinder is harder to make taste bad.

Flat burrs (two parallel discs) produce a tighter, more unimodal distribution, which tends to read as clarity and separation. You taste the bean more precisely, including its flaws.

For filter brewing and milk drinks, most people prefer conical. For light-roast espresso where you're chasing a specific flavour note, flat has the edge. Neither is "better" — and at the price points most home setups sit at, burr geometry matters less than alignment. More on that below.

3. Burr size: the spec everyone quotes, few understand

Burr diameter is usually the first number on the box and the last thing that should decide your purchase. Bigger burrs grind faster and hold speed more steadily, which helps consistency — but a well-aligned 38mm burr beats a sloppy 48mm every time.

We wrote a whole piece on this because it deserves one: Burr Size Explained.

The short version: 38mm is fine for filter and light travel use, 48mm is the practical sweet spot for a hand grinder that does espresso, and anything larger needs a motor.

4. Adjustment: the spec almost nobody advertises

This is where cheap grinders give themselves away, and it's the single most underrated number on the page.

How many clicks per rotation? Thirty clicks per turn means each step is a visible jump in grind size. That's workable for filter coffee. For espresso, where a two-second change in shot time matters, you want finer resolution: 100 clicks per rotation at 8–20 microns per step.

Internal or external? Internal adjustment means removing the catch cup or the whole hopper to change setting — and usually losing your reference point in the process. An external ring lets you move from a filter setting to an espresso setting and return to the exact number you left. If you brew more than one method, this is worth paying for.

Stepped or stepless? Stepped dials repeat settings exactly, which is what you want when you've found a recipe. Stepless gives infinite resolution but no repeatability unless you note the position. For home use, stepped is usually the better trade.

5. Capacity tells you who the grinder is for

Dose capacity is a proxy for household size.

• 15–20g: one drink. Ideal for solo brewing and travel.
• 35–40g: two drinks without refilling. The point at which a hand grinder stops being a chore.
• Over 40g: usually electric territory, or batch brewing.

Weight matters alongside capacity. Under 400g and the grinder goes in a backpack. Over a kilo and it lives on the counter, permanently.

Manual or electric?

This is the question most buyers actually arrive with, so let's be direct.

A hand grinder gives you more burr per dollar. No motor, no electronics, almost nothing to break. A $200 hand grinder out-grinds a $200 electric grinder, consistently. It's also silent, which matters at 6am in a small flat.

The cost is your arm. Grinding 18g at espresso fineness on a 38mm hand grinder takes the better part of a minute of steady cranking. On a 48mm burr, closer to 30 seconds. Do that twice a day and it's a ritual. Do it four times and it's a chore.

An electric grinder buys you repetition. If you grind for two people, brew several times a day, or have wrist or grip issues, a motor is not a luxury — it's the difference between using good gear and avoiding it.

One honest caveat about portable electric grinders: most are single-dose, battery-powered units aimed at travel. They're excellent for a hotel room or an office drawer and a poor substitute for a countertop grinder.

Match the grinder to how you actually brew

What to spend

Under $100

A 38mm hand grinder with a stepped dial. This is the best value in coffee equipment, full stop. It will out-perform any electric grinder at the same price.

$150–$250

A 48mm hand grinder with external adjustment. This is where you stop upgrading for a long time. If you brew espresso and filter with one grinder, buy here and skip the tier above.

$150–$300 electric

Single-dose home grinders with 48–64mm burrs. Worth it if volume or repetition is the constraint — not if you're chasing the last few percent of cup quality.

Three things to ignore

Bar numbers on machines. A 20-bar pump doesn't brew at 20 bar — the puck sees 9. It's a bigger number for the box.

"Military-grade aluminium." Durability marketing. It tells you nothing about the burr, which is what grinds the coffee.

RPM figures without context. Lower RPM is generally gentler, but RPM alone says nothing without burr size and geometry. A slow grinder with a bad burr is still a bad grinder.

The 60-second version

1. Burr, not blade.
2. 38mm for filter and travel; 48mm if espresso is involved.
3. Count the clicks. 100 steps beats 30 for espresso.
4. External adjustment if you brew more than one method.
5. Buy manual for value, electric for volume.