Saju compatibility · two sets of four pillars
Saju compatibility: how two birth charts meet
Enter birth datesEnter two birth dates (and birth times, if you know them) and this page works out the four things a traditional saju compatibility reading looks at: how the two day masters relate, how the two day branches (the “spouse palace”) meet, whether each chart fills the other’s missing elements, and, lightly, the zodiac pair.
There is no score and no “good” or “bad” verdict. Each relation comes with how tradition reads it and a few prompts worth talking through together.
Enter both birth dates
Enter each date as solar (Gregorian) or Korean lunar; a lunar date, leap month included, is converted to its Gregorian date first. Birth times are optional: leave one empty and that chart is read from three pillars.
Both birth dates are used only for the calculation in this browser. Nothing is stored or sent to a server.
What does a saju compatibility reading look at?
Saju (사주, the four pillars) describes a birth moment as eight characters: a heavenly stem and an earthly branch for the year, month, day and hour. A compatibility reading sets two charts side by side and looks at how their characters relate. The zodiac match many people know looks at a single character, the year branch; a saju reading goes further.
It starts with the day masters, the stems of the two day pillars, which stand for each person. Whether one nourishes the other, one shapes the other, or both share an element sets the basic tone, and a stem combination between them is read as a natural pull.
Next comes the day branch, called the spouse palace. Harmonies such as yukhap and samhap, or frictions such as chung and wonjin, are read as how daily life fits. The balance of the five elements and the zodiac pair complete the picture.
What this page calculates
From the two birth dates it works out both charts and then shows five things, all computed from fixed traditional tables: the same input always gives the same reading.
- Both sets of four pillars, day masters and element counts, side by side
- Day master relation: same element, nourishing or shaping (and in which direction), and any stem combination
- Day branch relation: yukhap, samhap, banghap, chung, hyeong, pa, hae, wonjin, or self-punishment for a shared branch
- Element balance: elements one chart lacks and the other holds, and elements both lack or both hold in abundance
- Zodiac pair: the relation between the two birth-year animals, counted from Ipchun (a lighter note)
The traditional relations at a glance
These are the rules the page applies. Stem combinations are five fixed pairs among the ten stems; branch relations are fixed pairs among the twelve branches. One pair can sit in two relations (寅 and 亥 are both yukhap and pa).
| Pair | Traditional reading | Transforms into |
|---|---|---|
| 甲己 | Upright middle | Earth |
| 乙庚 | Benevolence and righteousness | Metal |
| 丙辛 | Dignity | Water |
| 丁壬 | Kindness and long life | Wood |
| 戊癸 | Without sentiment (read as practical) | Fire |
| Relation | Pairs | Traditional reading |
|---|---|---|
| Yukhap (six harmony) | 子丑 · 寅亥 · 卯戌 · 辰酉 · 巳申 · 午未 | Natural partners; affection grows easily |
| Samhap (three harmony) | 申子辰 · 亥卯未 · 寅午戌 · 巳酉丑 | Three branches forming one energy (some count two as a half trine) |
| Banghap (same season) | 寅卯辰 · 巳午未 · 申酉戌 · 亥子丑 | Branches of the same season |
| Chung (clash) | 子午 · 丑未 · 寅申 · 卯酉 · 辰戌 · 巳亥 | Opposites on the circle; friction and change |
| Hyeong (friction) | 子卯 · 丑未 · 丑戌 · 寅巳 · 寅申 · 巳申 · 未戌 · 辰辰 · 午午 · 酉酉 · 亥亥 | Corrections that can turn sharp |
| Pa (break) | 子酉 · 丑辰 · 寅亥 · 卯午 · 巳申 · 未戌 | Plans and promises that go awry |
| Hae (harm) | 子未 · 丑午 · 寅巳 · 卯辰 · 申亥 · 酉戌 | Blocking each other’s partner; small hurts |
| Wonjin (resentment) | 子未 · 丑午 · 寅酉 · 卯申 · 辰亥 · 巳戌 | Irritation and misunderstanding without a clear reason |
How the charts are calculated: Korea Standard Time and solar terms
Both charts are calculated the same way as this site’s free saju. Years and months change at the solar terms, set by the Sun’s position, and the saju year begins at Ipchun in early February rather than on 1 January or at the lunar new year, so someone born in January or early February takes the previous year’s pillar and animal.
Solar terms are computed astronomically, converted to Korea Standard Time and checked against the dates published by the Korea Astronomy and Space Science Institute. Birth times are split into two-hour periods as entered; births between 23:00 and 23:59 keep the calendar date’s day pillar. Daylight saving time and longitude corrections are not applied.
The day master and day branch, the heart of a compatibility reading, depend on the date alone, so an unknown birth time leaves them unchanged; only the element counts drop to six characters.
Both birth dates stay in your browser
The two dates and times are used only for the calculation in this browser; nothing is stored or sent to a server. Closing or reloading the page clears the form and the reading.
The other person’s birth date is their personal data, so this page deliberately has no share link. To look at the reading together, share the screen or invite them to enter the dates themselves. If you have a saved saju, only your own date is filled in.
Analytics only record that this page was opened and that a reading was viewed; no birth date, time or result is ever included in an analytics event.
Relationship insights from psychology
Saju looks at a relationship through traditional symbols; personality questionnaires look at how two people actually think and express themselves. For communication styles see MBTI compatibility, for closeness and distance see the attachment style pairs, and for how you give and receive love see the love language pairs.
Frequently asked questions
Is it free?
Yes, and there is no sign-up. Enter two birth dates (solar or Korean lunar) to see the day master, day branch, element and zodiac relations; add birth times if you know them.
Can I check compatibility without a birth time?
Yes. The day master and day branch, the core of the reading, come from the date alone. Without a time the hour pillar stays empty and the element counts use six characters.
Is a clash or a wonjin a bad match?
No. Tradition reads them as places where friction can arise, not as a verdict. Any pairing becomes what two people make of it, so use the reading as a conversation starter.
Are the birth dates saved or shared?
No. Both dates and times are used only in this browser, never sent to a server, and the page creates no share link. Closing the page clears them.
This page summarises traditional saju compatibility readings for entertainment and self-reflection. It does not judge a relationship or predict the future, and it should not guide decisions about marriage, money or health. No pairing is better or worse than another: relationships are made by how people treat each other.
How to use this content
- This page is reference content for self-understanding and light interpretation, not a diagnostic or evaluative tool.
- It should not replace medical, legal, financial, or hiring decisions, and important choices need stronger evidence than a self-test.
- Use the result for reflection or entertainment only, and seek professional support first when distress or risk is involved.