Burrs are cutting edges and they dull with use.
The lifespan
Steel burrs — 300 to 500 kg of coffee for a home grinder, more for large commercial burrs.
Ceramic burrs — considerably longer, often twice that, though they are brittle and a stone will chip them.
Titanium or coated burrs — longer again.
What that means at home
A household using 500 g a week grinds 26 kg a year. Steel burrs at 400 kg would last fifteen years.
Most home grinders are replaced long before their burrs wear out. This is largely a commercial concern.
The signs
Slower grinding at the same setting. More fines, so brews taste muddier and more bitter. Needing progressively finer settings for the same shot time. More heat and noise.
Dull burrs crush rather than cut, which is exactly what widens the particle distribution.
What actually damages them
Foreign objects. A stone in a bag of coffee will chip a burr instantly, and it is the commonest cause of premature failure.
Specialty coffee is hand-sorted and this is rare; commodity coffee less so.
Grinding non-coffee — spices, sugar, anything harder than a bean.
Replacing them
Usually straightforward, and burr sets are sold as parts for good grinders.
Note the alignment and re-zero afterwards. New burrs need the setting re-established from scratch.
Last reviewed 8 August 2026