This Is What Your Dishwasher Does to Your Knives, According to the Experts

The one thing I've heard over and over again about taking care of my chef's knife and other kitchen knives is that I should never put them in the dishwasher—that it's a major no-no. Yet many times, I've been tempted to make like Ina Garten and stick everything in the dishwasher, including my knives.

Is it really that bad to put kitchen knives in the dishwasher? Well, yes, actually it is, according to the experts I talked to from the renowned German knifemakers, Wüsthof, and the Institute of Culinary Education.

Read on to learn the top three reasons you shouldn't put your knives in the dishwasher, even if you have the means to replace them frequently.

3 Reasons You Should Never Put Your Knives in the Dishwasher

1. Heat, Detergent, and Jostling Damage the Blade

"There are several reasons why we recommend not putting knives into the dishwasher," says Florian Rotondi, Deputy Head of Quality Management at Wüsthof. "First of all, the heat and the aggressive detergents and salts damage the knives. The blades become blunt and are more susceptible to rust."

Rotondi adds, "The worst place for knives in the dishwasher is the cutlery basket. Here the cutlery and the blades will keep hitting each other, which damages the blades.”

Shawn Matijevich, Lead Chef of Online Culinary Arts & Food Operations at the Institute of Culinary Education, echoes Rotondi about the damage that detergents, heat, moisture, and jostling can cause to your knives, and adds, "Most of the time this damage to the blade isn't visible as the knife edge is microscopic." In other words, even if you think your knives look fine when they come out of the dishwasher, they are likely damaged. 

2. Water Will Damage the Handle

Rotondi adds that moisture can penetrate into even the smallest cracks in your knife's handle, causing wooden handles to swell and become brittle. The last thing you want is for your knife's handle to break, especially if it happens while you are using it.

3. It’s Dangerous

Even if you are not worried about damaging your knives, putting sharp knives in the dishwasher poses a danger to children and even adults who might touch or grab a knife and cut themselves. And if you have pets who you just can't keep away from the dishwasher, a knife in there is a danger to them too. 

The Correct Way to Wash and Store Your Knives

"I have always hand-washed my knives because the heat, chemicals, and mechanical movement all work together to destroy them [in the dishwasher] in pretty short order," says Matijevich. As soon as you finish using your chef's knife, paring knife, or any other kitchen knife, wash it with warm, soapy water, rinse it well, and dry it immediately to prevent spotting and corrosion. Then put it away in a safe spot.

As for the best place to store your knives, Matijevich recommends a block or magnetic strip. "You definitely don't want to store them in a drawer with a bunch of other utensils," says Matijevich. "Every time you open the drawer everything bangs around and dulls the blade." 

The Takeaway

It's not a myth: You really should skip the dishwasher when it comes to your kitchen knives. Instead, hand wash them as soon as you are done using them, dry them immediately after washing, and store them properly in a block or on a magnetic strip.

If you follow these guidelines, your knives should last indefinitely. I'm still using a chef's knife I received as a gift more than 20 years ago and it looks as good and works as well as the day I got it—now I know I can at least partly credit its longevity to the fact that I've never put it in a dishwasher.