How to Pick a Moving Date

What Nalbadi does

Nalbadi lays what old-time Koreans looked at when choosing a date right on top of a calendar. Using the lunar date, the solar terms, and the day's ganji as inputs, it applies the traditional rules to that day and tells you only the name tradition gave that day.

We do not decide which days are good and which are bad here. Research on Korean date-selection custom reads its character as a habit of ordinary caution tied to the cycle of time, and we try to keep that same posture. We tell you what to look at; the decision is the reader's.

Every calculation follows a fixed rule. Ask about the same date any number of times and the answer does not change, and where a rule cannot reach, we say we do not know. There is no account to create and no birth date to send anywhere.

How to use the calendar

It opens on this month

The first screen is the month that holds today. The arrows at the top move a month at a time, forward and back, and carry across a year boundary. Each cell shows the lunar date in small type under the solar date, so you never have to look it up separately.

Pick a direction and more days open up

There are only six son-free days in a month, so a list of them is not much use if you cannot move on those days. That is why you can pick a direction, east, south, west, or north. Once you pick one, the calendar also counts the days Son rests in a different direction and tells you how many days open up that month. This is not a relaxation we invented; the tradition itself accounted for direction.

The direction you pick is also carried in the address. Copy that address and send it, and the person who opens it sees the same answer.

Pick a situation and the badges narrow down

The All, Moving, Wedding, and Contract buttons near the top filter which badges show on each cell to fit your situation. Pick Moving and only the direction, Mubangsu, and Singugan badges (all tied to moving) stay; pick Contract and Gongmang days stay; pick Wedding and Sibak days stay. Pick All to see everything at once.

There is more than the calendar

There is a separate page that shows only where Son rests today, and a map that lays out the whole year on one page so the ten-day cycle shows up as a pattern. A free printable one-pager is also there, ready to put on a fridge.

Where Son is today

What this app calculates

From here on, each item explains which rule a badge on the screen comes from. We only included rules whose method we could verify in a primary source; anything we could not verify is named, with the reason we left it out, under Background below.

Son-free days and Son's direction

Only the last digit of the lunar date matters. A day ending in 9 or 0, meaning the 9th and 10th, 19th and 20th, or 29th and 30th of the lunar month, is marked son-free. A day ending in 1 or 2 marks Son resting in the east, 3 or 4 the south, 5 or 6 the west, and 7 or 8 the north, and that direction is printed in small type. Because this is set by the lunar date rather than the solar one, it falls on no particular day of the week.

Mubangsu

A single day: the 9th of the second lunar month. Because the date is fixed on the lunar calendar, its solar-calendar position moves every year. The 9th of a leap second month is not counted.

Samsalbang and Daejanggunbang

These directions are set per year rather than per day. Looking at the year's earthly branch, Samsalbang falls east in years of Sa-Yu-Chuk, west in Hae-Myo-Mi years, south in Sin-Ja-Jin years, and north in In-O-Sul years. Daejanggunbang falls east in Sa-O-Mi years, west in Hae-Ja-Chuk years, south in Sin-Yu-Sul years, and north in In-Myo-Jin years. The calendar prints both directions for the current year in one line near the top. The year is counted from Seol (Lunar New Year).

Gongmang and Sibak days

Both of these depend on the day's ganji. Gongmang falls on twelve specific ganji days: Eulchuk, Gapsul, Eulhae, Gyemi, Gapsin, Eulyu, Imjin, Gyesa, Gapo, Imin, Gyemyo, and Imja, and tradition records them as days people put off money-bound dealings like a sale or a contract. Sibak days depend on the year's heavenly-stem group together with a specific lunar month and ganji day, so they do not fall in every month and some years have none at all.

Singugan

A period from Jeju Island tradition. It runs from five days after Daehan to three days before Ipchun, and is marked accordingly. Because it needs solar-term dates, it only shows up for years we have a solar-term table for; other years show nothing.

Samjae

A reckoning that groups the earthly branch of one's birth year into threes by Samhap, counting three years at a time. Pick your zodiac animal and the calendar tells you whether this year is the first of those three years (Deul-samjae), the second (Jal-samjae), or the last (Nal-samjae). Old records mention both a reading of misfortune and, alongside it, a Boksamjae reading of fortune, and we print both rather than settle on one. Your pick is used only on screen and is never saved or sent anywhere.

Sources and range of the calculation

Lunar conversion and the day's ganji use Korean lunisolar calendar data as-is, and the Ipchun and Daehan dates are fixed into a table checked against our Saju calculation engine. The day's ganji was cross-checked with that engine at five points before use. Year pages run from 2024 through 2030, and month pages from 2025 through 2028, because we only build a page where our solar-term table reaches.

How to read the screen

Badges on a cell

A son-free day carries a Son-free badge, and any other day carries the direction Son rests in, such as Son: east or Son: south. Mubangsu, Gongmang, Sibak, and Singugan each carry their own name. A badge is a name tradition gave that day, not our own verdict.

What "clear" means

Once you pick a direction, cells split into two kinds. A son-free day is clear no matter which way you go. A day marked Clear this way means Son rests in another direction, so tradition treated the way you mean to go as open. A day marked Son this way means Son sits in the direction you picked. Neither is a verdict of good or bad; it is only a record of how tradition read that direction.

Days marked unknown

A day outside our lunar-calendar data range shows a question mark and is marked unable to check. Such a day is not counted as an open day either. We treat saying it is fine when we do not know as the worst possible answer.

Why holidays are not shown

Public holidays are not marked right now, and we note plainly that holiday data is not yet in place for the year. We took down the source we started with after re-reading its usage terms and finding they did not fit our use, and we are preparing to refill it from a source or statute with clear terms. We would rather say plainly that holidays are missing than let the calendar look complete when it is not.

Background

What kind of being was Son?

In this tradition, Son is an old folk figure said to bring harm to people. It was said to travel through east, south, west, and north following the lunar date, then rise to the sky and leave no direction occupied on days ending in 9 or 0. Those two days each cycle came to be called son-free days, and the custom grew of doing a big gathering-event, like moving or a wedding, on them. One full cycle takes ten days.

The fuller reckoning included direction

Today, people often shorten this to just the two days ending in 9 and 0, but the form recorded in dictionaries also tracks direction. Son's position was set for every single day, so even on a day that was not son-free, a day was still considered fine as long as Son was not in the direction you meant to go. That is why this calendar marks a direction every day.

What we left out

Search for a moving date and you will also run into terms like the nine-direction rule, Ogwibang, and Gachwimyeolmun days. We did not include these because we could not verify their method in a primary source. Saenggibokdeok, a compatibility method, checked out in principle but we could not obtain a complete table for it, so we left it pending. We think naming what we do not include, and saying why, is better than dressing up something we could not verify.

Sources

We consulted the entries for son-free day, Mubangsu day, Samsalbang, Daejanggunbang, Singugan, and Samjae in 국립민속박물관 한국민속대백과사전 (the National Folk Museum of Korea's Encyclopedia of Korean Folk Culture). We also consulted Kim Man-tae's paper 한국 택일풍속의 전승양상과 특징 (Transmission and Characteristics of Korean Date-Selection Customs, 2009, vol. 32 no. 1). Sources differ on whether that journal's name is 정신문화연구 or 한국학, so until we can confirm it from the original cover, we print both rather than settle on one.

Frequently asked

Is it good to move on a son-free day?

We do not answer that. We only tell you what old-time Koreans called that day and why. Judging good or bad is not this calendar's job, and the decision is always the reader's.

Does that mean I should not move on any other day?

The fuller form of the tradition ties in direction. A day was still considered clear if Son was not in the direction you meant to go. Pick a direction and the calendar counts those days too, so the number of usable days grows quite a bit.

Can I use this without knowing the lunar calendar?

Yes. Every cell shows the lunar date alongside the solar one. The one marked lunar is that day's lunar date, and one marked leap is a leap month.

Why is some day marked with a question mark?

It falls outside the range our lunar-conversion data reaches. Rather than fill in a guess, we say we cannot check it.

Is any personal information saved?

The zodiac animal you pick for Samjae is used only on that screen and is never saved or sent anywhere. No account is needed either. See our Privacy Policy for the details.

I'd like my full Saju read too

This calendar only handles the date-based rules that are the same for everyone. If you want a precise reading that also takes your birth time into account, our sister service Gwirae's full fortune calendar does that.