15materials5appliances100%cited & datedhow we verify

Is it oven safe? Find any material in the grid.

One matrix, five appliances. Read across a material to see whether it's safe in the microwave, oven, air fryer, dishwasher, or freezer — each answer with its condition and a last-verified date.

Explore the matrixHow we source & verify

15

materials

5

appliances

100%

cited & dated

01 — the matrix

Material × appliance safety matrix.

Safety verdict for each material in each appliance. Verdicts are Safe, Conditional, Unsafe, or Not applicable; conditional cells state their limit.
MaterialOvenMicrowaveAir fryerDishwasherFreezer
Borosilicate glass (Pyrex)SafeSafeConditionalNo lid; avoid shockSafeSafe
Soda-lime glassConditionalNo sudden temp changeSafeNo metal trimConditionalThermal-shock riskSafeConditionalLeave headspace
Mason jar (canning glass)UnsafeNot bakewareConditionalLid off; not maker-approvedUnsafeNot oven-safe glassSafeConditionalStraight-sided; headspace
Ceramic / stoneware (glazed)SafeIf rated oven-safeSafeNo metallic glazeConditionalIf it fitsSafeConditionalAvoid shock
Cast ironSafeUnsafeMetal arcsConditionalIf seasoned & fitsUnsafeStrips seasoning, rustsConditionalDry to prevent rust
Stainless steelSafeUnsafeMetal arcsSafeSafeSafe
Aluminum foilSafeUnsafeSparks, fire riskConditionalWeighted, off elementConditionalCan discolorSafe
Parchment paperConditionalTo ~420°FSafeConditionalWeighted; not preheatN/ASafe
Wax paperUnsafeWax melts, smokesSafeShort burstsUnsafeSmokes, can igniteN/ASafe
Styrofoam (polystyrene, #6)UnsafeMelts, fumesConditionalOnly if labeled safeUnsafeMeltsUnsafeWarps on heatSafe
Polypropylene container (#5)UnsafeMeltsSafeVent the lidUnsafeMeltsConditionalTop rackSafe
Zipper bag (polyethylene)UnsafeSoftens at 230°FConditionalDefrost/reheat; vent 1 inUnsafeMelts; fan lifts itUnsafeMaker says hand-washSafeFreezer-grade for long storage
Paper plate (plain)UnsafeFire riskSafeNo metallic printConditionalWeighted, shortN/ASafe
Cardboard (corrugated)UnsafeIgnites near 451°FConditionalPlain only; short burstsUnsafeFan lifts it onto elementN/AConditionalOuter box; not a barrier
Silicone bakewareSafeTo ~450°FSafeSafeSafeSafe

02 — method

How we verify.

Every answer is grounded, in order, in the manufacturer's spec for a named product, official USDA/FDA guidance, then established material science — never an invented temperature. Conditional means safe within the stated limit. When in doubt, defer to the symbol on your item.

How we source & verify ›

03 — by appliance

Browse by appliance.

Prefer to start from one appliance? Each hub lists every material we've tested for it, with the temperature ceiling and failure mode.

MicrowaveSparks, melting plastic, and what's actually microwave-safe.OvenTemperature ceilings for dishes, cookware, and containers.Air fryerFoil, parchment, and what the fast-moving hot air can and can't handle.DishwasherHeat, detergent, and why the top rack matters.FreezerCracking glass, expansion, and safe freezing containers.Materials & symbolsRecycling numbers, safety symbols, and melt points explained.

04 — latest answers

Latest item answers.