The smell is alive, which is why covering it never works
Shoe odor is bacteria eating the sweat you left them. Every fix that lasts either dries the shoe or kills them. Everything else is perfume.
Public conversations full of people comparing remedies that contradict each other. What made a page possible was not any single remedy but the pattern underneath them all — and no count appears here, because there is none behind it that would mean anything.
Shoes do not smell. Bacteria smell, and shoes are where they live: warm, dark, damp, and restocked with sweat every day you put them on.
That one fact sorts every remedy you have ever been told. Anything that lasts either dries the shoe out or kills what is living in it. Everything else is perfume on a compost heap.
It explains the thing that makes this subject so confusing, which is that the same tip gets wildly opposite reviews. Tea bags are the clearest case: plenty of people swear by them, and plenty report that their shoes went from smelling of feet to smelling of feet and tea. Both are telling the truth. Dry tea absorbs some moisture and adds a scent; it does not kill anything. Whether that reads as success depends entirely on which of the two you were hoping for.
The same test explains the freezer. A night in a sealed bag in the freezer does knock the smell back, and a recurring complaint is that it returns once the shoes warm up — which is what you would expect from cold that suspends bacteria rather than finishing them.
The unglamorous one that actually works
The thing people kept coming back to is also the least satisfying: give them a full day to dry before wearing them again. Shoes need something like twenty-four hours to dry out properly, and a shoe worn every single day never gets there. Two pairs in rotation solves a problem no spray solves, and it is the move people keep arriving at after everything else. If a second pair is out of reach, the next best thing is pulling the insoles out and standing the shoes somewhere airy the moment you take them off — it will not buy a full day, and it buys something.
Stack the cheap things on top of it and most cases are done. Pull the insoles out so both sides can breathe. Baking soda overnight, tipped out before you wear them. Wool socks rather than cotton, because wool carries moisture away from skin instead of holding it there. Dry between your toes before the socks go on.
For a shoe that is already past that — a synthetic trainer, not leather — isopropyl alcohol sprayed inside kills the colony outright, and may need doing more than once.
That is the whole toolkit, and it is mostly free. What it is not is a smell you can spray away, because the smell is not a thing. It is something living, and it is being fed.
Common questions
So which of the remedies actually work?
Sort them by what they do and the noise clears. DRYING: rotating pairs so nothing gets worn two days running, pulling the insoles out, cedar shoe trees, silica packets, a low heat source. KILLING: isopropyl alcohol on synthetics, and a night in the freezer inside a bag — which is argued about, because the smell often returns as they warm, exactly as you'd expect if the cold suppressed the bacteria rather than finishing them. ABSORBING: baking soda overnight, which genuinely takes moisture and odor out and is close to free. And MASKING: scented sprays and the widely-repeated tea bag trick, which others report leaves shoes smelling of tea rather than of nothing. The absorbers and the maskers get taken for each other, which is why the same tip has such wildly different reviews.
What about my feet, rather than the shoes?
That's where the sweat comes from, so it's the better place to intervene. The moves that came up repeatedly: wool socks instead of cotton, because wool moves moisture off skin instead of holding it against it; drying between the toes before the socks go on rather than after; keeping nails short; and filing dead skin off the heels and soles, since that hard skin is organic matter sitting in a warm damp box all day. A powder with zinc oxide in it came up as the answer for stubborn cases — it makes the surface hostile to the bacteria rather than scenting them. One thing to avoid on the way there: talc. Talc-based powders carry their own health questions and there is no reason to reach for one when zinc oxide is what people actually recommended.
Full tip: https://findangel.org/tips/the-smell-is-alive · FindAngel.org — free, always.