Burrs don't fail on a schedule — they dull slowly, quietly stealing shot quality for weeks before anyone notices. Here's how to tell it's actually the burrs, not your technique.
01You keep grinding finer for the same result
If you find yourself creeping the grind setting finer month after month just to hit the same shot time you used to get at a coarser setting, the burrs are losing their cutting edge and you're compensating for it without realizing.
02The grinder runs louder, hotter, or slower
Dull burrs have to work harder to cut the same amount of coffee. A rougher pitch, more heat at the chute, or a noticeably longer grind time for the same dose are all signs of increased friction from worn edges.
03The visual check
Grind a small amount and inspect it on a white surface. New, sharp burrs produce a fairly uniform particle size. Worn burrs produce a mix of larger chunks and fine dust at the same time — visibly less consistent even to the naked eye.
04Flat, muted flavor even with fresh beans
Uneven particle size means uneven extraction — some particles over-extract while others under-extract at the same time, muddling the cup even when your beans and recipe are otherwise dialed in.
05How long burrs actually last
Lifespan is usually measured in kilograms of coffee ground rather than calendar time — commonly cited figures are roughly 450kg for steel burrs and around 340kg for ceramic in home use, though this varies by grinder and burr quality.
If you replace your burrs, expect to re-dial your grind setting from scratch — a fresh burr set changes your zero point, so your old numbers won't carry over directly.