What's that smell? Diagnose it in about a minute

Tell us what it smells like, where it's strongest, and when it happens. We'll rank the likely causes, flag anything urgent, and give you safe checks to confirm it.

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What does it smell like?

Pick the closest. Safety-critical smells are listed first.

How this diagnostic works

Every answer adds or removes weight from a library of known causes: dried-out drain traps, water heater reactions, damp basements, AC drain lines, overheating outlets, and dozens more. The ranking is deterministic. The same answers always give the same result, and every cause shows why it was ranked where it is.

Safety comes first. If your answers point at a possible gas leak, fire, or people feeling unwell, that warning shows above the ranking. A smell can't tell you about carbon monoxide, because CO has no smell, so keep CO alarms on every level of your home.

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