8 Things You Should Think Twice About Putting in a Dishwasher — And Why
A dishwasher can save a huge amount of time, but not everything in your kitchen belongs inside it.
High temperatures, strong detergents, water pressure and heated drying can damage certain materials. And while a dishwasher can damage an item, that doesn’t necessarily mean it will literally “explode.” The dramatic image in the viral post should be treated as an illustration, not proof that the pictured incident actually happened.
Here are 8 common items that are better washed by hand:
1. 🪵 Wooden utensils and cutting boards
Wood can absorb moisture and repeatedly expand and contract under the dishwasher’s heat. Over time, this can cause warping, cracking or loss of the finish. Product Help | Whirlpool
👉 Wash wooden items by hand and dry them promptly.
2. 🔪 Good kitchen knives
Dishwasher detergents, heat and repeated washing can dull or damage sharp blades. Knives can also move around and potentially damage the dishwasher racks. Whirlpool
👉 Hand-washing is usually the better option for quality knives.
3. 🥘 Cast-iron cookware
A dishwasher can strip away the seasoning that protects cast iron, leaving the surface vulnerable to rust. Whirlpool
👉 Clean cast iron by hand and maintain its seasoning.
4. 🍳 Some non-stick cookware
Heat, detergent and repeated washing can contribute to deterioration of some non-stick coatings. The correct approach depends on the manufacturer’s instructions, so don’t assume every non-stick pan is dishwasher-safe. Whirlpool
5. 🥂 Crystal and delicate glassware
Delicate glass and crystal can be particularly vulnerable to breakage, etching or cloudiness from repeated dishwasher cycles. Whirlpool
👉 Ordinary sturdy drinking glasses are generally different—always check the manufacturer’s recommendation.
6. 🥉 Copper and certain decorative metals
Copper can develop discoloration or pitting in the dishwasher. Brass, bronze, pewter and some other metals can also be damaged by heat and detergent. Whirlpool
7. 🥤 Thin or disposable plastic
Some plastics simply aren’t designed to withstand dishwasher temperatures. They can warp or deform, particularly during heated drying. Product Help | Whirlpool
👉 If plastic is marked dishwasher-safe, follow the manufacturer’s instructions; many plastic items are best placed on the top rack. Product Help | Whirlpool
8. ☕ Insulated travel mugs and containers
Some insulated cups and containers rely on seals or insulation that can be damaged by dishwasher heat and water. Whirlpool
👉 Unless the manufacturer specifically says they’re dishwasher-safe, wash them by hand.
⚠️ One important thing about the viral photo
The broken glass shown in the picture doesn’t establish that a particular dishwasher caused the incident, and there’s no basis from the image alone to conclude that someone put the “wrong” item inside.
Also, glass itself isn’t automatically unsafe for dishwashers. Many ordinary glasses and tempered glass items are dishwasher-safe. The important question is whether that particular item is rated dishwasher-safe. Product Help | Whirlpool
✅ The golden rule
If you’re unsure, check the manufacturer’s instructions or the dishwasher-safe symbol before putting the item inside.
And never assume that “dishwasher-safe” means every cycle is safe—heated drying and high-temperature cycles can be harder on certain materials. Product Help | Whirlpool
👇 Which of these have you accidentally put in the dishwasher before?
