How to Use the Sambok Dates Calculator
Sambok — meaning "three periods of lying low from the heat" — is a Korean traditional concept naming the three hottest stretches of summer: Chobok, Jungbok, and Malbok. It's not a fixed date on the modern calendar; it's set by combining the sun's position (the summer solstice) with a 10-day cycle from the old East Asian sexagenary calendar, so you can't simply look it up on a regular calendar. Select a year above and this calculator works out that year's three dates for you, based on the solstice and the start of autumn (Ipchu).
Traditionally, Chobok falls on the third "gyeong" day after the summer solstice, Jungbok on the fourth, and Malbok on the first gyeong day after Ipchu (roughly early August). Because gyeong days repeat every 10 days, Jungbok and Malbok are usually 10 days apart — but depending on exactly when Ipchu lands, some years stretch that gap to 20 days, a pattern known as "wolbok."
This custom has no scientific basis — it's a long-running cultural tradition, similar to how many cultures mark the peak of summer heat with their own customs. On Sambok days, many Koreans eat hot, nourishing food like samgyetang (ginseng chicken soup), following an old belief that "fighting heat with heat" helps the body cope with the season. Think of this tool as a guide to a fun piece of Korean culture rather than a scientific forecast.
Frequently Asked Questions
Sambok refers to the three hottest days of the Korean traditional calendar — Chobok, Jungbok, and Malbok. It's a cultural custom, not a scientific measurement, and many Koreans eat warming foods like samgyetang (ginseng chicken soup) on these days.
Sambok dates follow a traditional 10-day 'gyeong' day cycle. Depending on when the start of autumn (Ipchu) falls that year, the gap between Jungbok and Malbok can stretch to 20 days instead of the usual 10 — a pattern traditionally called 'wolbok'.