Glass vs. Ceramic Air Fryers

Three answers to one worry

Almost everybody who searches for this is really asking one question: how do I avoid the nonstick coating? That question has three legitimate answers on the market, and they are not variations on a theme — they are genuinely different objects with different trade-offs.

• Glass. The food sits in a borosilicate glass vessel and the heating unit sits on top. There is no coating, so there is nothing to scratch, flake or wear out.
• Ceramic coating. A thin inorganic layer, usually a silica-based sol-gel, baked onto an aluminum basket. It is still a coating — it just is not a fluoropolymer.
• Stainless steel. Bare metal, no coating, nothing to degrade. Almost nobody makes an air-fryer basket this way, for a practical reason covered below.

The background on why people care at all — PTFE, PFOA, the wider PFAS family, and what the FDA actually publishes — is in are air fryers toxic. This page assumes you have already decided you want to avoid a fluoropolymer coating and is about which of the three formats to buy.

Glass: the only format with nothing to degrade

Glass is the honest answer to the coating question because it removes the coating from the equation rather than replacing it with a better one. On the Ninja Crispi, the whole cooking vessel is borosilicate glass — the same material class as laboratory glassware and ovenproof bakeware — and Ninja states in its own listing that the containers are free of PFAS, PTFE and nonstick chemical coatings. The set ships a 4-quart container and a 6-cup container with snap-lock lids, so the thing you cooked in is also the thing you store and reheat in.

What you give up is shape and weight. A glass container is heavier than an aluminum basket, it has no nonstick release at all so eggs and cheese need oil or parchment, and the format caps out small: 4 quarts is the biggest vessel in the set. Ninja publishes no wattage for the Crispi's PowerPod, so we cannot put a running-cost figure on it, and we do not estimate one.

The full field, including the glass-bowl machines that use a different layout, is in best glass air fryers.

Ceramic: good enough for almost everyone, with one caveat

A ceramic coating behaves like nonstick, cleans like nonstick and is not a fluoropolymer. For most buyers that is the whole requirement, and it is why ceramic is the format we recommend by default.

The caveat is that "ceramic" and "PFAS-free" are not the same claim, and the difference is visible in the listings on this site. The Cosori TurboBlaze, the Cosori TWINFRY and the Typhur Dome 2 each publish an explicit PFAS-free statement about the coating. The Ninja AF101 and the Cosori Pro LE describe a ceramic coating and publish no PFAS claim at all. Both groups are selling you a ceramic basket; only one group has committed to a statement about what is not in it. If the claim matters to you, buy from the group that makes it.

The second caveat is durability. A sol-gel layer is thin, and the things that kill it are well known: metal utensils, aerosol cooking sprays, abrasive scrubbing, and repeated dishwasher cycles even on machines rated dishwasher-safe. That is a care problem rather than a safety problem, and it is the whole of what to do when an air fryer coating comes off. The coating category in full, including which maker publishes which claim, is best ceramic air fryers.

Stainless steel: mostly a marketing word on air fryers

This is the part the category is least honest about. "Stainless steel air fryer" almost always describes the housing, not the surface your food touches. The Ninja DZ401 is sold as a stainless steel air fryer and has a stainless body — and its cooking surface is a nonstick layer, which Ninja separately states is 100% PFAS-free. Those are two different facts about two different parts of the machine.

Genuine bare-stainless cooking surfaces do exist in this corner of the market, but they turn up on multi-cookers rather than air fryers: the Instant Pot Duo Crisp has an 18/8 stainless inner pot with a tri-ply bottom, oven- and stovetop-safe, and its air-fry function works in that pot. Oven-style machines are a middle case — the Cuisinart TOA-70 publishes a stainless steel easy-clean interior, while the accessories that go in it include a ceramic non-stick grill plate.

The reason bare stainless baskets are rare is simple: without a release layer, food welds to hot perforated metal and a basket with hundreds of holes is miserable to clean. That is a real trade, not a conspiracy. If stainless is non-negotiable, the realistic route is a pressure cooker with an air-fry lid, or an oven-style machine with a stainless cavity — see best air fryer toaster ovens, where interior height rather than coating is the deciding spec.

How to choose between them

In order of how often it applies:

• You want a normal air fryer and no fluoropolymer. Ceramic with a published PFAS-free claim. The Cosori TurboBlaze at 6 quarts, 11.8 × 14.4 in and a 2-year warranty is the default; the Typhur Dome 2 is the large flat-basket version.
• You want zero coating and will accept a smaller machine. Glass. The Ninja Crispi, with the caveat that 4 quarts is the ceiling and there is no nonstick release.
• You cook for four and want two zones. The Ninja DZ401 at 10 quarts, with the 100% PFAS-free nonstick claim — the format is covered in best dual-basket air fryers.
• You genuinely want bare metal. Instant Pot Duo Crisp, and accept that you are buying a pressure cooker that also air-fries.

One thing worth saying plainly: none of the three is a health emergency to switch to. The FDA's published position is that intact nonstick cookware is not a dietary exposure concern, and a ceramic basket in good condition is not meaningfully different from a glass one in use. Buy glass if you want the certainty, buy ceramic if you want the convenience, and read best non-toxic air fryersif you want the ranked field across all three formats. The label claims themselves — PFAS, PTFE, PFOA, "ceramic", BPA — are decoded in what PFAS-free actually means.