Coffee is oily, and oil plus fine particles builds up on burrs and in the chute. The symptoms are indistinguishable from worn burrs: slower grinding, more fines, muddier flavor.
Weekly
Empty the hopper, take out the top burr if your grinder allows it, and brush both burrs and the chamber with a stiff dry brush. Five minutes.
Do not use water. Damp burrs corrode and any residual moisture makes a paste with the next grind.
Monthly
Grinder cleaning tablets — food-safe pellets you run through as if they were beans. They absorb oils and carry the residue out. Grind and discard a small dose of coffee afterwards.
Rice is sometimes recommended and is a bad idea: it is harder than coffee and can damage burrs, and it is not what the grinder was designed to cut.
Every few months
Take the burrs out properly, brush everything, and inspect for chips. On a grinder like a Baratza, the guides are published and it is a kitchen-table job.
Oily dark roasts
They gum up burrs much faster. If you drink very dark, oily beans, double the frequency.
The tell
If shots have slowly needed a coarser grind over months to keep the same time, you either have dull burrs or dirty ones. Clean first — it is free.
What people want to know
How do I clean the grinder in a super-automatic machine?
Most are not meant to be opened. Vacuum the bean hopper and the ground-coffee chute, and use the machine's own grinder-cleaning product only if the manual allows it.
Last reviewed 30 October 2026