Those two-number labels on cookware boxes are not marketing fluff — they are shorthand for the alloy's actual composition, and that composition determines how your pan behaves on day one of cooking and on year ten of ownership. The first number is chromium, the second is nickel. An 18/8 pan contains roughly 18% chromium and 8% nickel; an 18/0 pan has the chromium but no nickel. That single difference drives corrosion resistance, magnetism, and induction compatibility.
Decoding Stainless Steel Grades: 18/0, 18/8, 18/10, and Beyond
The retail labels and the industrial numbers describe the same metals. As cookware manufacturer Changwen explains, 18-8 is another name for 304 stainless steel, one of the most widely used and trusted grades in the food service industry. The same mapping applies to 18/10, which also falls within the 304 family. The AISI numbers — 304, 316, 430 — are the materials-science designations and, as one cookware guide notes, they tell you more, including whether molybdenum is in the alloy.
What makes steel "stainless" in the first place is chromium. According to the British Stainless Steel Association, cited in a cookware buying guide, stainless steels are corrosion-resistant steels with at least 10.5% chromium, and elements such as nickel and molybdenum further affect corrosion resistance and performance. Nickel enhances durability and gives the metal its lustrous finish, while chromium provides the corrosion resistance. The "8" in 18/8 refers to that nickel content.
Then there is 18/0, which corresponds to the 430 grade. It is a different metallurgical family — ferritic rather than austenitic — and that distinction matters most when you turn on an induction burner, as we will see below.
Stainless Steel Cookware Grades: Quick Comparison
The table below classifies the common grades by composition and maps them to the two characteristics that matter most in a kitchen: how well the steel resists corrosion, and whether a magnet will stick to it — the practical test for induction compatibility.
| Grade (retail & SAE) | Composition (Cr/Ni) | Corrosion Resistance | Magnetic (Induction Ready?) | Common Kitchen Uses |
|---|---|---|---|---|
| 18/0 (Type 430) | ~18% chromium, no nickel | Less corrosion resistance than 304 grades | Yes — magnetic, suitable for induction | Flatware, dishwasher-safe utensils, magnetic outer layer of clad pans; less common as a primary cooking surface |
| 18/8 (Type 304) | ~18% chromium, 8% nickel | Excellent, from chromium and nickel content | Generally non-magnetic when annealed; may become slightly magnetic after cold working; not typically suitable for induction unless combined with a magnetic layer | Everyday cookware, food service equipment, utensils; a trusted grade in the food service industry |
| 18/10 (Type 304) | ~18% chromium, 10% nickel | Excellent, with the higher nickel supporting durability and corrosion resistance | Same as 18/8 — austenitic and generally non-magnetic | Higher-end cookware and flatware, especially for acidic-food contact |
The pattern that emerges is a genuine trade-off rather than a simple hierarchy. The 304-family grades win on corrosion resistance and durability; the 430 grade wins on magnetism. This is why many quality pans use both.
Practical Implications for Your Kitchen: Corrosion and Induction
Nickel is what separates a pan that shrugs off tomato sauce from one that needs more care. Because 18/8 and 18/10 carry higher nickel content, they offer better durability and corrosion resistance, which — as Xometry's materials guide puts it — makes them "perfect for cookware that comes into contact with acidic foods." An 18/0 pan is still suitable for basic cookware applications, but without nickel it may be more prone to corrosion.
Induction works in the opposite direction. Citing the Machinery's Handbook, Pi Fabricators explains that austenitic grades like 304 are nonmagnetic in the annealed condition but become slightly magnetic after cold working such as bending, drawing, or machining, while ferritic grades like 430 are magnetic in all conditions. The practical test is simple: if a magnet sticks strongly to a stainless part, it is most likely a 400-series ferritic grade; if it does not stick or sticks only weakly, it is most likely a 300-series austenitic grade.
This is why 18/0 steel is almost never used as a cooking surface — its primary cookware role is the magnetic outer layer of induction-compatible clad pans, where it lets the induction coil engage. A 304 interior for food contact and a 430 exterior for the burner is the standard engineering solution, so a non-magnetic cooking surface does not mean a pan will not work on induction.
Beyond the Grade: Food Safety and Cookware Construction
On safety, the common grades clear the bar. Xometry's guide states plainly that 18/8, 18/10, and 18/0 stainless steels are all suitable for cookware, and that none of them contain lead. Changwen likewise describes 304 as the gold standard for items that contact food or beverages, citing its corrosion resistance and long-term durability. One caveat worth knowing: a cookware guide notes that alloy differences can matter for leaching behavior and, for a small but real subset of cooks, nickel exposure — a consideration for anyone with a nickel allergy weighing an 18/0 flatware set against an 18/10 one.
Construction matters as much as the grade, because the label tells you only about the steel, not how the pan is built. The same guide distinguishes between fully clad pans, in which layers of different metals extend up the sides, and pans with an encapsulated or disc base, where the layered construction is limited to the bottom. A disc-base pan can perform well for most tasks but may heat less evenly up the walls — a difference between a budget skillet and a premium one that the "18/10" stamp alone will never reveal.
Choosing Your Stainless Steel Cookware: A Practical Decision
Select stainless steel cookware based on its grade to match your cooking needs, prioritizing magnetic properties for induction and higher nickel content for better corrosion resistance against acidic foods. The presence of "18/0" or "430" on cookware indicates induction compatibility, while "18/8" or "18/10" (Type 304) signifies superior corrosion resistance for general cooking.
Before your next purchase, run the magnet test on any pan you already own: a strong stick means a 400-series layer that will engage an induction burner, and a weak or absent stick points to a 304 cooking surface built for corrosion resistance. On a clad pan you should find both — and that combination, not the box label alone, is the mark of cookware designed to last.
Sources
- Stainless Steel Grades Comparison: 18-8 vs 201 vs 304 vs 430 - Complete Guide - Changwen Cookware Manufacturer
- Best Stainless Steel Cookware Grades: 304 vs 316 vs 18/10 Explained — Cupindy
- Stainless Steel Grades: 304 vs 316 vs 18/0 — Vettedclean
- 18/8 vs. 18/10 vs. 18/0 Stainless Steels: What Are the Differences? — Xometry
- Stainless Steel Grades Chart: 304 vs 316, 410, 430 — Pi Fabricators
