How Can Water Damage a Knife?

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Updated August 2026 · 6 min read · UK Japanese knife specialists

A good knife is an investment, so it's natural to worry about ruining it. Water is the thing most people ask about — and the honest answer is that a splash of water while you cook won't hurt a quality knife at all. What causes real damage is standing water, the dishwasher, and putting a knife away wet.

Our knives are made from high-carbon stainless Japanese steel (VG10 and AUS-10), so they resist corrosion far better than the traditional carbon-steel blades of old. But "rust-resistant" isn't "rust-proof", and the handle needs looking after too. Here's exactly what water does — and the simple routine that keeps a knife pristine for decades.

Does water actually damage your knives?

It depends on how much, and for how long. A quick rinse is fine. The problems start with prolonged exposure — a knife left sitting in a wet sink, or put away before it's dry.

The blade

Stainless steel earns its name from the chromium in the alloy, which forms an invisible protective layer that resists rust. That's why our Japanese-steel knives shrug off everyday water contact. But that protection has limits: leave any steel in contact with water or trapped moisture long enough and corrosion will eventually begin, showing up as small rust spots. Older traditional carbon-steel blades are far more prone to this — one more reason modern high-carbon stainless is the easier knife to live with.

The handle

Composite and resin handles cope well with water, though prolonged soaking can still work into the join where the handle meets the tang and loosen it over time. Natural wooden handles need the most care: wood swells when wet and shrinks as it dries, and that repeated movement can crack a handle. Keep wooden handles out of standing water and dry them promptly.

Do stainless knives really rust?

They can, but rarely, and almost always because of how they're treated rather than the odd splash — think a knife left in the sink overnight, dried salt or acidic food residue, or a damp knife sealed in a block. Treat the blade reasonably and rust simply won't be an issue.

Why the dishwasher is the real enemy

If there's one habit to avoid, it's this. The dishwasher combines everything a good knife dislikes at once:

Dishwasher cycles run hot, the high-pressure jets bang the blade against plates and racks (dulling and chipping the edge), and the harsh detergents are abrasive enough to dull and discolour a fine edge over time. For a hard, thin Japanese edge that's a fast route to damage — and for very brittle blades like ceramic, it can be terminal. There's more detail in our guide on whether you can put chef knives in the dishwasher.

How to wash and dry a knife properly

The whole routine takes seconds: wash the blade by hand in warm, soapy water with a soft sponge, rinse, then dry it immediately with a tea towel — edge away from your fingers. Then put it straight back into its storage spot rather than leaving it on the draining board.

Don't leave knives in the sink. Beyond the corrosion risk, a blade hidden under soapy water is a genuine hazard for your fingers, and it can bang against other items and chip. And dry before storing — a wet knife sealed in a block traps moisture, which can lead to rust or even mould.

If a rust spot does appear

Don't panic — surface rust usually lifts off easily. Our guide on how to remove rust from a Japanese chef knife walks through it, and the full Japanese knife care guide covers everything else. For storage options, compare a knife rack vs a knife block.

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