Yes — pet hair and fur compost fine. It's organic material (keratin, the same fibrous protein in human hair and nails), and while it breaks down more slowly than soft food scraps, it's a legitimate compost addition rather than something that needs to go in the trash.
Quick Answer
Brush-fulls of dog or cat hair, fur from grooming, even hair swept up off the floor — all compostable. It decomposes slower than kitchen scraps because keratin is a tougher, more fibrous protein, but it does break down, and in the meantime it acts as a "brown" (carbon) material that helps balance wetter additions.
Why Pet Hair Takes Longer to Break Down
Hair and fur are made of keratin, a structural protein that's naturally resistant to decomposition — it's the same reason hair takes a while to break down in general, compared to something like a vegetable scrap. This isn't a problem, just a timing consideration: hair added to a compost pile will still be identifiable weeks after softer material has fully broken down. Given enough time, it does decompose fully.
How to Add It So It Breaks Down Faster
- Break up clumps and mats before adding. Tightly packed fur — the kind that comes off a brush in one solid clump — resists airflow and moisture the same way any dense, matted material does. Loosening it up before adding speeds decomposition meaningfully.
- Mix it in rather than adding it in a thick layer. A concentrated layer of hair can mat down and shed water rather than absorbing it. Distributing it through the rest of the pile works better.
- Treat it as a "brown" (carbon) material if you're balancing a backyard pile — it pairs well with wetter kitchen scraps the same way shredded paper or dry leaves do.
When to Skip It
- Recently flea- or tick-treated hair or fur: give topical treatments time to break down or wash off before composting brushed fur, since some treatment chemicals aren't something you want concentrated in compost headed for a food garden. A few weeks after treatment is a reasonable buffer.
- Hair from an animal currently on other medications, for the same reason — when in doubt, skip that batch rather than guess.
Otherwise, routine grooming fur and shed hair don't carry any special risk.
Does This Apply to Human Hair Too?
Yes — human hair is the same basic material (keratin) and composts the same way, with the same slower timeline. Both compost fine together if you're combining sources.
Frequently Asked Questions
Does pet hair compost as fast as food scraps? No — keratin is more resistant to decomposition than soft food material, so hair takes noticeably longer. It does fully break down eventually, especially in a hot, actively managed pile.
Can I compost fur from flea-treated pets? Wait a few weeks after topical flea or tick treatment before composting brushed fur, so the treatment has time to break down rather than ending up concentrated in the finished compost.
Should I compost hair in clumps or loose? Loose. Break up mats and clumps first — tightly packed hair resists airflow and moisture, which slows decomposition further.
Can I put pet hair in an electric composter? In small amounts mixed with other scraps, yes, though pet hair isn't food waste and isn't the primary intended input — a backyard pile or dedicated compost bin is generally the better home for it, especially in larger quantities.
Is human hair compostable the same way? Yes, same material (keratin), same slower decomposition timeline as pet hair.
The Bottom Line
Pet hair is compostable — it just takes patience. Break up clumps, mix it into the rest of your compost rather than layering it thick, and give recently flea-treated fur a few weeks before adding it. What would otherwise be trash becomes one more carbon-rich material doing useful work in the pile.
References
- U.S. Environmental Protection Agency. Composting at Home. https://www.epa.gov/recycle/composting-home
- Cornell Waste Management Institute. Compost Chemistry and the Biology of Decomposition. https://compost.css.cornell.edu/chemistry.html
