Can you take dry shampoo on a plane?

On a domestic flight only the quantity limits apply. On an international flight the liquid rule comes on top.

Domestic flights in Japan

The 100ml liquid limit does not apply.

International flights from Japan

Each container 100ml or less, all of them inside one transparent re-sealable bag of 1 litre or less, one bag per person.

Japan's liquids list restricts liquids, gels and aerosols. A powder dry shampoo is none of these, so the 100ml limit does not apply to it.

A can of dry shampoo is screened as an aerosol and a shaker of dry shampoo powder as a powder, and the 2 forms meet different limits.

Hong Kong and the TSA name it, Japan does not

Hong Kong's CAD writes dry shampoo into its example of toiletry articles, straight after hair sprays. The TSA titles its entry Dry Shampoo (aerosol), so the entry is about the can. The hair care row in Japan's list of restricted items runs from hairspray and hair tonic to hair colour and bleach and leaves dry shampoo out.

Where Japan's liquids list meets a powder, it exempts it

Japan's liquids list for international flights applies to the liquid, the gel and the aerosol, and to articles that lose their shape outside the container. Powders show up on it only as exceptions: bath products are listed except the granule-type and powdered ones, and soup stock except cubes or powder. A dry shampoo powder has no row on the list.

A large powder goes in its own bin at US checkpoints

The TSA handles powder by size. Powder-like substances greater than 12 oz. / 350 mL must be placed in a separate bin for X-ray screening. They may require additional screening and the container may need to be opened. The 3.4oz/100 ml carry-on figure belongs to the entry for the aerosol can.

Australia asks whether the powder is organic or inorganic

Australia's Home Affairs limits inorganic powders on international flights: containers of 350 mL or 350 g or less, and no more than 350 mL, 350 g per person. Organic powders have no limit, and its list of organic examples includes most cosmetics. Powders may have to be presented separately at the screening point, without a re-sealable plastic bag.

At UK airports the can is a liquid and the powder an X-ray matter

GOV.UK counts sprays as liquids and gives hairspray and spray deodorants as examples, which is where a can of dry shampoo falls. For the powder form it has a different sentence: powders in hand luggage can obstruct images on x-ray machines, and the bag may need to be checked again manually by security.

The carry-on answer for dry shampoo is the same in all 7 other places we checked. The limits themselves are not identical, so read the row for the country you fly from.

Each row comes from that authority's own page. Airlines can be stricter, and the screening officer has the final say.

What to do

Move dry shampoo to the bag you check in before you reach security, within the checked-baggage limits above. Narita Airport states that anything given up at the checkpoint is discarded and cannot be returned.