To clean a burr coffee grinder, unplug it, empty the hopper, lift out the top burr and brush the grounds and oily dust out of the burrs, chamber and exit chute. Wash only the hopper and bin, if your manual allows. Skip the rice. Every four to six weeks suits most home burr grinders, and oily dark roasts need it sooner.
The job takes about ten minutes once you've done it once. What takes longer is the first time, when you're working out which parts come out and which ones you shouldn't touch.
How often should you clean a coffee grinder?#
Manufacturers don't agree on one number, so pick the shortest interval that matches your grinder and your beans.
| Situation |
How often |
| Baratza burr grinders, routine clean |
Every 4 to 6 weeks |
| Moccamaster KM5, inside of the grinder |
Every 3 to 6 months |
| Dark, shiny, oily roasts |
More often than the above |
| Switching to a very different coffee |
Brush the chamber before the first grind |
| Grinder hums but nothing comes out |
Now (it's clogged) |
Baratza's grinder cleaning guide sets the four-to-six-week routine and says dark roast drinkers will need to clean more often because the oils build up faster. Moccamaster's KM5 cleaning page asks for an inside clean every three to six months, again sooner with dark or oily beans.
If you drink a medium roast and grind once a day, every six weeks is a reasonable place to start. Open it up at that point and look. A light film of dry dust means you could stretch it. A sticky brown paste on the burr teeth means you waited too long.
How to clean a burr grinder#
- Run the grinder empty for a few seconds to push out what's sitting in the burrs, then unplug it.
- Note or photograph the grind setting. Some grinders lose their setting when you pull the burr, and it's annoying to dial back in from memory.
- Empty the hopper and take it off.
- Remove the upper burr the way your manual describes (usually a twist and lift). On Baratza's Sette models the lower burr comes out too. On most others, leave the lower burr where it is.
- Brush the burr teeth, the burr carrier and the inside of the chamber with a stiff, dry brush. A vacuum nozzle held near the chamber pulls out the fine dust you loosen.
- Clear the exit chute. This is the part people forget, and it's where grounds pack in and cause clogs. Poke it gently with a brush or a wooden skewer, never a knife.
- Wash the hopper and grounds bin in warm soapy water if your manual says they're washable. Baratza allows this for its hopper and bin. Moccamaster says to wipe the KM5 hopper with a damp cloth and keep grinder parts out of the dishwasher. Dry everything completely.
- Refit the burr, check it seats properly, reset your grind setting and grind a small dose of beans to throw away before you brew.
Keep water away from the burrs, the chamber and the motor housing. Moccamaster tells owners not to immerse the grinder in water at all, and a damp burr chamber plus fresh coffee dust makes a paste that's harder to remove than what you started with.
Why you shouldn't clean a grinder with rice#
The rice trick gets passed around a lot. Moccamaster lists it alongside dishwashers and soaking as things not to do. Uncooked rice is far harder than a roasted coffee bean, and the burrs and motor weren't built to crush it. It also leaves its own dust in the chamber, which you then have to brush out anyway.
If you want something you can run through the grinder, use cleaning tablets sold for that purpose. Baratza calls them optional and says they help absorb leftover oils, which is why they suggest them for people grinding mostly dark roasts. Tablets are a quick in-between clean. They don't replace brushing out the chamber.
How to clean a blade grinder#
Blade grinders are simpler, but check one thing first: does the bowl lift out, or is it fixed to the motor base?
If it lifts out and the manual says it's washable, wash it in warm soapy water and dry it before it goes back on. If the bowl is fixed, unplug the grinder, tip out the loose grounds, then brush and wipe the bowl and blades with a barely damp cloth. Never hold a fixed-bowl grinder under the tap. The blades are sharp, so wipe from the center outward and keep your fingers off the edges.
Signs your grinder needs cleaning sooner#
- Fresh beans taste flat or slightly bitter, and nothing else about your brew changed.
- Grounds clump or stick to the chute instead of falling cleanly.
- Output slows down, or the grinder makes more noise than usual.
- You can see an oily sheen on the burrs or a crust in the chute.
- The motor runs but nothing comes out.
That last one is a clog. Stop the grinder, unplug it and follow your model's unclogging steps. Don't keep feeding beans in hoping it'll clear itself. Moccamaster's guide says to make sure the dispensing chute is completely clear before testing again.
Keep it separate from the coffee maker#
Grinder cleaning is a dry job. Brewer cleaning is a wet one. Treat them as two tasks so water never ends up near your burrs. When it's time for the brewer, see how to clean and descale a coffee maker. And if you're wiping down the grinder housing, a clean, dry microfiber cloth picks up coffee dust without leaving lint.
A recurring reminder every six weeks in ChoreLists.com is enough for most people. If you open the grinder and it's still clean, push the next one out.