Can I get the musty smell out of an old book without damaging it?

Usually yes, if you go slow and dry. Air the book out, then seal it in a container with baking soda or activated charcoal sitting next to it for a week or two. The damage happens when people rush it with sprays, heat, or powder poured on the pages. Keep liquids and direct heat away from the paper and you can clear most of the musty book smell safely.

Does the baking soda go on the book or beside it?

Beside it, never on it. Put the book and an open dish of baking soda or a bag of charcoal in the same sealed bin, with the absorber not touching the pages. Powder poured between pages is hard to remove and can leave residue, especially if the paper is still a little damp.

Will freezing a book kill the musty smell?

Freezing can slow active mildew growth, which is why archives sometimes freeze water-damaged books to buy time. It does not remove the smell, though, and condensation when the book warms back up can add moisture. For odor, drying and absorbing works better than the freezer.

How long does it take to air out a musty book?

A lightly musty paperback often improves in a few days of good airflow and clears over a week or two in a sealed container with an absorber. A book that sat damp for years may take several rounds of fresh absorber, and some of the deep smell may never fully leave if the paper itself has degraded.

Is old-book smell the same as mildew smell?

No. The dry, sweet old-book smell is the paper aging, and it is harmless and mostly permanent. The sour, damp smell is mildew from trapped moisture, and that is the one you can remove by drying the book and pulling the odor out with an absorber or, for a whole collection, professional treatment.

How to remove the musty book smell from old books and paper

Mildew & Musty · By Odor Removal Experts · Updated June 2026 · Cleveland and Northeast Ohio

That musty book smell is old paper holding moisture. Paper is mostly cellulose and lignin, and as it ages the lignin slowly breaks down and gives off the sweet, dusty note people know as old-book smell. That part is harmless. The problem starts when a book sits somewhere damp. Moisture soaks into the pages, mildew starts growing on the covers and page edges, and the gentle smell turns sour and sharp. To get it out you dry the paper, pull the odor off it with airflow and an absorber, and then keep the book somewhere that stays dry.

On the jobs we get called for around Greater Cleveland, the worst cases are inherited libraries and boxes that sat in a basement through a few humid summers. One paperback you can usually save at home over a week or two. A few hundred books that all carry the same reek is an air problem and an item problem at the same time, and that is the point where home tricks stop working.

The short answer

Old books smell musty when trapped moisture lets mildew grow on the paper, glue, and covers. Dry the book with airflow first, then seal it in a container with baking soda or activated charcoal sitting beside it for a week or two. The dry, sweet old-book smell is harmless aging and mostly permanent.

Two smells: harmless paper aging, and removable mildew from damp
Dry the book fully with airflow before any absorber step
Seal it with baking soda or charcoal beside it, never on the pages
Skip sun, sprays, and ozone; they mask or damage the paper

Why old books smell musty

There are two different smells people lump together. The first is the aging of the paper itself. Old paper releases organic compounds as the lignin and cellulose break down, which is the dry, slightly sweet smell of a used bookstore. The second is mildew, and that one is a moisture problem. When humidity gets into the pages and stays there, mildew feeds on the paper, the glue, and any dust on the surface. That is what makes a box of old books smell sour and damp instead of just old.

Knowing which one you have matters. The dry old-book smell is mostly permanent and harmless, and a lot of people actually like it. The sour, damp mildew smell is the one you can remove, because you are removing the moisture and the growth that feed it.

lignin and cellulose breaking down (the dry old-book smell)
humidity trapped in the pages
mildew on covers, spines, and page edges
old glue and binding adhesives
dust that fed growth during damp storage

Fixes to try at home first

For one book or a small stack, start with air and time.

Stand and fan each book. Set books upright with the pages fanned open in a dry, well ventilated room, out of direct sun.
Move air across them. A small fan speeds things up a lot, and airflow alone pulls a surprising amount of the damp smell out of paper that is not badly mildewed.
Give it several days. This is slow work measured in days, not minutes, so let the airflow keep running.
Dry before you absorb. If the book was damp recently, get it fully dry first, because a book still holding moisture will keep smelling no matter what you put near it.

The same drying-first rule applies to soft items that picked up the smell in storage. If you are also dealing with linens or fabric that sat in the same box, the method to get the mildew smell out of clothes and towels follows the same idea of drying first and absorbing what is left.

How to use baking soda or activated charcoal

An absorber pulls the lingering smell out of paper without putting anything wet or scented on the book. The safe way is to seal the book in a container with the absorber sitting beside it, never touching it. Put the book in a plastic bin or a large sealable bag. Add an open dish or box of baking soda, or a bag of activated charcoal, in the same container but not against the pages. Close it up and leave it for a few days to a couple of weeks, checking now and then.

Activated charcoal works the same way and tends to be cleaner to handle. The absorber does slow work, so the longer you leave it sealed, the more it pulls. If the smell is mostly gone after a week, you are done. If it has barely moved, the odor is deeper than a passive absorber can reach.

seal the book in a bin or bag with the absorber
keep baking soda or charcoal beside the book, not on it
leave it sealed for several days to two weeks
never sprinkle powder between the pages
swap in fresh absorber if the smell is strong

Never pour powder onto the pages

Do not pour baking soda onto the pages or sprinkle it between them. It is hard to get back out, it can leave a residue, and on damp paper it sticks. Keep the absorber in the same sealed container, beside the book, not against it.

What does not work, and what can wreck a book

A few popular fixes do more harm than good. Long stretches in direct sun fade the cover and warp the pages, and they only mask the surface smell for a day. Spraying a book with any liquid, including fabric refreshers, adds moisture, which is the exact thing that caused the smell. We also never use ozone, and we never use a cover-up scent. Ozone is sold as a quick odor fix, but it does not reach moisture trapped in paper, and we do not mask a smell and hand it back to you. Masking fades, and the musty book smell comes right back.

If a book is already structurally damaged by long-term damp, with soft, wavy, or stuck pages, be honest with yourself about it. The paper has changed, and some of that smell is now part of the material. You can reduce it, but you may not get it all the way back to new.

no long sessions in hot, direct sun
no sprays or liquids on the pages
no ozone and no masking scents
accept that badly damaged paper may not fully recover

When a whole box or inherited library needs a pro

One book is a home project. An inherited library, a damp box of hundreds, or a whole room of books that all smell the same is a different job, because the smell is in the air of the room and in every item at once. That is the kind of work we get called for. We treat the air and the items together with green, non-toxic methods. HEPA filtration with activated-carbon scrubbing pulls the musty load out of the room air. Occupied-safe hydroxyl generators break down the odor compounds without ozone. For items, controlled thermal fogging and absorber work reach what a passive dish at home cannot.

We will also tell you when a book is too far gone to fully save, instead of promising a miracle. If the room itself smells musty and the books are only part of it, the source is usually moisture in the space, and our musty odor removal work goes after that at the same time. For storage going forward, the same dry-air habits that keep a musty smell out of a closet and clothes keep a book collection fresh.

air and items treated together
HEPA plus activated-carbon air scrubbing
occupied-safe hydroxyl, no ozone
honest call when paper is too damaged to fully recover