Most knives are not truly dishwasher safe, even when labeled otherwise, because heat, detergents, and clanking against other items dull edges and damage handles.
For the full breakdown, see our best Dishwasher Safe Steak Knives guide.
Whether a knife survives the cycle depends on three things: the handle material, the steel quality, and how you load the rack. Here’s what the manufacturers actually say, what ruins blades, and how to wash them the right way.
What Knife Makers Actually Say
Ask anyone who makes knives and the answer is almost always the same: hand wash. Victorinox notes that while its household knives with synthetic handles are technically dishwasher-safe, the company still recommends washing all large knives by hand. ZWILLING goes further, advising hand washing with lukewarm water and mild soap, and noting its knives are only safe at dishwasher temperatures of 55°C and lower, with blades kept separate from other items.
The pattern is consistent across the industry. “Dishwasher-safe” on a label usually means the knife won’t melt or rust to pieces in one cycle, not that it will stay sharp. The heat, the detergent, and the rattling all work against the blade.
What Damages Knives In The Dishwasher?
Three forces work together to wreck a knife in the dishwasher:
- Metal-on-metal contact — blades knocking against other utensils chips and dulls the edge with every cycle.
- Harsh detergents and high heat — these cause staining, pitting, discoloration, and can deteriorate handle materials over time.
- Wooden handles — these should never go in the dishwasher unless the manufacturer explicitly says otherwise; the heat and moisture cause cracking and warping.
Leaving knives in after the cycle ends or using the “rinse and hold” soak setting extends their exposure to moisture and steam, making things worse.
How To Wash Knives Without Ruining Them
Handle Materials And Dishwasher Risk
Not all handles are created equal, and the material changes your risk level:
References & Sources
- Victorinox. “Knife Care Tips.” Official guidance on dishwasher use and hand washing for household knives.
- ZWILLING. “Knife Use and Care.” Covers temperature limits, hand washing guidance, and separation during dishwasher cycles.
- Prestige. “Dishwashing Guide.” Explains why wooden-handled knives should not go in the dishwasher.
