자막 or 더빙: working out whether you will understand the film
Korean cinemas subtitle foreign films rather than dubbing them, which is good news — until the film is Korean, or animated. The rules, and the two words that tell you which screening you booked.
Updated
The default is subtitles, and that works in your favour
Korea subtitles foreign films rather than dubbing them. A Hollywood release plays in English with Korean subtitles underneath, exactly as it would at home minus the text at the bottom of the frame.
For an English-speaking visitor this is the single most useful fact about Korean cinema. Roughly half of any given box office top ten is foreign, and most of that is American — meaning there is almost always something on that you can follow completely, without planning.
It also means a French, Japanese or Spanish film screens in its original language with Korean subtitles only. If you do not read Korean and do not speak the original language, that is a film to skip.
Korean films at ordinary screenings have no subtitles at all
This is the part that catches people out. A Korean film at a normal commercial screening carries no subtitles in any language, because the audience does not need them. There is no English-subtitled print sitting in the projector waiting to be selected.
It is not a rule with no exceptions — some cinemas in Seoul run occasional subtitled showings, and film festivals subtitle everything — but the exception has to be sought out. It is never the default.
The practical version: if the film is Korean and you do not speak Korean, assume you will not follow the dialogue unless the listing explicitly says otherwise. The language note on each film page here is derived from the producing country for exactly this reason.
Animation is released twice, and you have to pick
Family animation is the one category released in two versions that screen side by side on the same day at the same cinema: 자막 (jamak), the subtitled version with the original soundtrack, and 더빙 (deobing), dubbed into Korean.
Both appear in the listings as separate showings of what looks like the same film. Booking the wrong one is easy and the difference is total — a dubbed print has no English on the soundtrack at all.
These two words are worth memorising by shape if not by sound. 자막 means you hear the original; 더빙 means you hear Korean. They appear next to the showtime, not in the film's title.
Why the official data cannot tell you this
Korea's public film data records one film per release, not one record per print. A film that goes out in both a subtitled and a dubbed version is a single entry, with a single set of admissions covering both.
There is no language field in the data at all, and no showtime service — showtimes are held by the cinema chains rather than published centrally.
So any language guidance derived from official records, including the guidance on this site, is an inference from the producing country rather than a fact read off a feed. It is right often enough to be useful and it is not a guarantee. The cinema's own listing for the specific showing is the authority.