The dishwasher-safe symbol
The most reliable indicator is a symbol on the product itself — typically a plate or glass inside a dishwasher. Some brands use text like 'dishwasher safe' or 'top rack safe' printed right on the item or its packaging. Flip the item over, check the bottom or the inside of the lid; manufacturers always place this information where it won't wear off easily.
If you see a crossed-out dishwasher symbol (a plate with a line through it), the item should be hand washed only. Take this warning seriously — it means the dishwasher will genuinely damage the item or degrade it faster than hand washing would.
Understanding material labels
Materials themselves tell a story. Stainless steel, tempered glass, and most ceramics can handle the heat and water of a dishwasher. Delicate materials like wood, cast iron, crystal, and many non-stick coatings cannot. If you're unsure what material you're holding, look for care labels on the packaging or the manufacturer's website.
Gold or silver trim, decorative paint, and hand-glazed details are almost always hand-wash-only. The dishwasher's heat and harsh detergent can strip these finishes, leaving them dull or damaged. Enamel-coated items vary — enameled cast iron can handle a dishwasher (though manufacturers often don't recommend it), while some delicate enameled cookware should stay in the sink.
Manufacturer care instructions
When in doubt, check the brand's website or the product manual. Major manufacturers like Yeti, Stanley, and Le Creuset provide explicit guidance on their dishware. If the care tag is missing or faded, Google the product name and 'dishwasher safe' — most popular items have settled information online.
Don't assume a similar product from the same brand will have the same care. Older Stanley bottles, for example, are hand-wash only, while the newer Quencher H2.0 is dishwasher safe. Always verify the specific product you own.
When in doubt, hand wash
If you can't find a clear answer, hand washing is always the safest option. A few minutes at the sink protects the item's finish, color, and longevity. Items that are borderline — like expensive water bottles or non-stick pans — are worth the extra care, even if they're technically dishwasher safe.