Reading compatibility through the four pillars means comparing two charts on three axes: how the two day stems relate by element, which of harmony, clash, punishment or harm holds between the two day branches, and whether combining the sixteen characters fills a gap either chart has on its own. This tool calculates all three, names the position each one lands in, and relays how tradition has read that position. It assigns no score.
Only the first person's details are stored, in this browser, sharing the store with the Saju chart tool so they need entering once; Forget clears them. The second person's details are somebody else's and are never saved.
No sex is asked for. It only affects the direction of the luck cycles, and there is nowhere for it to enter a compatibility calculation.
The character standing for a person in the four pillars is the stem of the day pillar, the day master. The first axis compares the two day masters by element. There are five elements, and between any two of them only three relations exist: same, producing, controlling.
Producing runs wood to fire to earth to metal to water and back, each becoming material for the next. Controlling skips a step: water over fire, fire over metal, metal over wood, wood over earth, earth over water. Nothing in the rule says which is preferable.
What matters here is direction. A producing relation still has a giving side and a receiving side; a controlling relation still has a pressing side. So this tool never writes only producing — it writes which way the flow runs.
The second axis is the lower character of the day pillar, branch against branch. Fixed pairings exist among the twelve. Six harmony binds six pairs; six clash sets six pairs directly opposite, six positions apart. Punishment is the misaligned position, and six harm is a weaker six pairs.
Most combinations are none of the four. Sixty-six pairs can be made from twelve branches, and harmony, clash and harm account for six each, so no particular relation is the commonest answer. That is not a bad result, only a sign this axis has nothing to say.
Triple and directional harmony are left out. They need three branches, so two day branches cannot settle them. Some schools count a half-harmony from two, but the scope of that varies, and only what the calculation settles goes on screen.
One chart is eight characters, and counting their elements gives a spread across five slots. Where a chart holds none of some element, that is its imbalance. The third axis puts the two spreads together.
The substantive part is an element one chart lacks and the other has. When tradition talks about two people supplementing each other, this arrangement is usually what it means. An element missing from both stays missing, since combining cannot supply it.
This axis is no more a verdict than the others. The count uses four stems and four branches only, so it differs from schools that count hidden stems, and what an even spread means for a relationship is interpretation rather than rule.
A compatibility score is the commonest shape around this search term. Yet no traditional text assigns points to ten gods or branch relations and tells you to total them. A score comes not from the rules but from weights its author chose.
That matters because a number looks like a calculation. Producing, with a six harmony is a statement you can check; 87 out of 100 is not. Put an uncheckable number where a result belongs and the trustworthiness of the checkable parts goes down with it.
So this screen carries no large number. It names the position on each of three axes and leaves how to weigh them to the reader. That is the point at which this page stops making somebody else's decision.
Check whether the two day stems match first. A day stem can shift by one depending on how the birth time is corrected — whether true solar time is applied, and whether a birth after 23:00 rolls into the next day's pillar. Shift the stem and every judgement after it changes.
If the stems match, the remaining difference is interpretation. One source reads the same controlling relation as friction and another as supplying form. Neither has the arithmetic wrong; there is simply more than one tradition.
To see the corrections themselves, open the evidence block in the Saju chart tool. It lists what was corrected, which is where the two answers parted.
It does not predict how a relationship will go. What it calculates is which positions two charts occupy under the rules, and it then relays how tradition has read those positions.
It does not pass judgement on a person. A screen that concluded a pairing was bad would be easy to build, and one such sentence can genuinely damage something real. The traditional descriptions do not go that far either.
It makes no date-selection or naming judgements. Those are separate rule systems; this page handles the three axes that compare two charts.
Three axes here: the element relation between the two day stems (same, producing, controlling), the relation between the two day branches (six harmony, six clash, punishment, six harm), and the combined element spread of both charts. All three are facts fixed by calculation; interpretation sits on top of them separately.
There is none. A figure like 87 out of 100 comes from no traditional rule — it comes from weights whoever built the calculator chose. An unverifiable number placed where a calculation belongs undermines the calculations around it, so this tool names each position and never adds them up.
Saying so goes further than the traditional descriptions do. A clash is the position directly opposite on the ring of twelve, read as one of movement and change that does not stay put. No primary source says it means parting. This tool stops where the sources stop.
Different calculations entirely. Name compatibility reduces the stroke counts of two names down a ladder as a game; this reads the element and branch relations of charts derived from birth dates. The two disagreeing is normal.
What this tool bases its numbers on, and how far those numbers go.
1. Day-stem relation: compare the two stems' elements on the producing cycle (wood→fire→earth→metal→water) to get same, producing or controlling, plus the direction. 2. Day-branch relation: look the pair up in the six-harmony, six-clash, punishment and six-harm tables (triple and directional harmony need three branches and are excluded). 3. Element spread: count four stems plus four branches per chart by element and add them. Charts come from the same buildChart the Saju tool uses.Day stems Xin (metal) and Gui (water) → metal produces water, so producing, running from the first person to the second. Day branches Hai and Wei → Hai-Mao-Wei is a triple harmony needing three, so two characters give no relation.