316 contains 2–3% molybdenum (Mo); 304 does not. This makes 316 far more resistant to chloride/saltwater corrosion (marine, coastal, pools, road salt) and certain acids, while 304 is the economical general-purpose grade.
| Chemical Composition (wt%) | ||
| Element | 304 | 316 |
| Chromium (Cr) | 18.0–20.0 | 16.0–18.0 |
| Nickel (Ni) | 8.0–10.5 | 10.0–14.0 |
| Molybdenum (Mo) | - | 2.0–3.0 |
| Carbon (C) | ≤0.08 | ≤0.08 |
| Iron (Fe) | Balance | Balance |
The Core Difference: One Key Ingredient
304 Stainless Steel: Contains 18% chromium and 8% nickel. It's the most common "18/8" stainless steel.
316 Stainless Steel: Contains 16% chromium, 10% nickel, and 2-3% molybdenum.
That molybdenum is the game-changer. It's an alloy that dramatically improves resistance to chlorides (salt) and acids.
Corrosion Resistance
304: Excellent for indoor / fresh water / dry outdoor; good in food-grade environments. Poor in high chloride (saltwater, coastal air, pools) → risk of pitting/crevice corrosion.
316: Superior chloride resistance (Mo stabilizes passive film); better resistance to sulfuric/phosphoric acids and high-temperature oxidation. Ideal for marine, coastal, chemical, medical (sterilants).
Typical application comparison
Kitchen: sinks, cookware, cutlery, appliances
Indoor architectural trim, railings
Food processing equipment (non-chloride environments)
Automotive trim
Marine: boat fittings, propellers, rigging
Coastal: railings, fasteners, cladding
Chemical: pipes, tanks, valves (acids, solvents)
Medical: surgical instruments, implants, sterilizers
Swimming pool hardware, desalination equipment
Choose 304 if: Indoor/dry outdoor, fresh water, food service (no heavy chloride), budget-sensitive.
Choose 316 if: Saltwater/marine, coastal, pools, chemical exposure, medical sterilization, or long-term durability in harsh conditions.
