Which one is for visas and which one is for study
KIIP (사회통합프로그램, Korea Immigration & Integration Program) is the Ministry of Justice's free language and culture course for foreign residents. It has stages 0 to 5 (0–4 are Korean language, 5 is Understanding Korean Society), each ending in a test. Unlike TOPIK it is a course-plus-test programme, not an exam, and only residents of Korea can take it.
Study (D-2, D-4 visas), scholarships (GKS), skilled work (E-7) — TOPIK. Universities do not accept KIIP as proof of language ability.
Changing visa and settling: F-2-7 points visa, F-5 permanent residency, F-6 marriage visa, naturalisation (귀화) — KIIP is the stronger option. Completing KIIP stage 5 exempts you from the naturalisation language test and adds points for F-5/F-2. TOPIK also earns points, but KIIP FULLY satisfies some requirements.
A TOPIK certificate exempts you from the KIIP placement test (사전평가) and places you directly into a higher stage: TOPIK 1 → stage 2, TOPIK 2 → stage 3, TOPIK 3 → stage 4, TOPIK 4–6 → stage 5 (one stage above the level you have already proven). The mapping is maintained in the Ministry of Justice notice — check socinet.go.kr. In other words, getting TOPIK 4 first and then joining KIIP skips all 400 hours of the language stages.
Not yet in Korea, or planning to study or apply for a scholarship — TOPIK, there is no alternative. Living in Korea on a work or family visa and planning to stay long-term — KIIP, because it is free and more effective for visa points. The two are not mutually exclusive: most people get TOPIK 3–4 first (for work and settling in), then go for F-5 or citizenship with KIIP 5.
TOPIK and KIIP get confused constantly, and the confusion costs people money and months. They are run by different parts of the Korean government for different reasons.
TOPIK is run by NIIED under the Ministry of Education and measures Korean language proficiency. KIIP — the Korea Immigration and Integration Program, 사회통합프로그램 — is run by the Ministry of Justice and is a course you attend, with an assessment attached, covering language and Korean society for people who live in Korea.
You need TOPIK for university admission and graduation, for scholarships including GKS, and for points on several visa routes. It is the document you send with an application from abroad.
You need KIIP if you are already living in Korea and heading towards permanent residency or naturalisation. Completing the programme satisfies language and civics requirements that would otherwise mean a separate exam, and it can shorten parts of the process. It is not a substitute for TOPIK on a university application.
TOPIK is a single exam on a fixed date that you can sit without any course. KIIP is a course with levels 0 to 5, attended in person or online at an assigned centre, with a placement test at the start and an assessment at the end of each stage. Level 5 covers Korean society rather than language.
Because KIIP is attendance-based, it takes months by design. TOPIK takes one morning.
Partly, and only in one direction. A TOPIK level can exempt you from parts of KIIP — the placement test uses it — so a Level 4 certificate can put you straight into a later stage of the programme. KIIP completion does not give you a TOPIK level, and no university will accept it instead.
If you are outside Korea and applying to study, you need TOPIK, and KIIP is not available to you. If you are living in Korea on a family or work visa and thinking about permanent residency, KIIP is the route, and TOPIK is optional but useful because it shortens it.
If you are in Korea and also applying to a university, you need both, for different parts of your life. MOON keeps a separate centre for each so the materials never get mixed up.