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日主 · the day stem as reference point

Day Master calculator

Find the stem at the top of the day pillar. That one coordinate supplies a phase and polarity, then acts as the comparison point for the Ten Gods relationships elsewhere in a Four Pillars chart.

A scholar's relationship chart with a central Day Master tablet and ten paired medallions
日主One stem becomes the reference for nine visible stem comparisons.

Birth moment → day stem

Find the chart's reference stem

The date is required. Time is optional except near 23:00, where the late-Rat and civil-midnight day conventions can disagree.

Needed to test the 23:00 day edge.

19 February 1901–8 February 2100 · birth data is not saved

Your day stem opens here

Enter a real birth date to locate its day pillar on the uninterrupted sixty-day sequence.

What the calculation does

A day pillar first, a Day Master second

The calculator locates the date in the sexagenary day count, applies the declared day boundary, and then reads the pillar's first character as the Day Master. It does not infer a personality from the stem alone.

  1. 01

    Locate the day

    The date belongs to one fixed two-character stem–branch day coordinate.

  2. 02

    Test the Rat-hour edge

    At 23:xx, the late-Rat reading and civil-midnight reading are both retained.

  3. 03

    Read the first character

    The day's Heavenly Stem becomes the phase-and-polarity reference used by Ten Gods.

Ten possible reference stems

Every Day Master already has a full record

Each stem record contains its six cycle pillars, hidden-stem positions, fixed partners and complete Ten Gods comparison map.

  1. 01甲 Jia

    Yang Wood · one of ten possible day-stem reference points

    Full Jia record →
  2. 02乙 Yi

    Yin Wood · one of ten possible day-stem reference points

    Full Yi record →
  3. 03丙 Bing

    Yang Fire · one of ten possible day-stem reference points

    Full Bing record →
  4. 04丁 Ding

    Yin Fire · one of ten possible day-stem reference points

    Full Ding record →
  5. 05戊 Wu

    Yang Earth · one of ten possible day-stem reference points

    Full Wu record →
  6. 06己 Ji

    Yin Earth · one of ten possible day-stem reference points

    Full Ji record →
  7. 07庚 Geng

    Yang Metal · one of ten possible day-stem reference points

    Full Geng record →
  8. 08辛 Xin

    Yin Metal · one of ten possible day-stem reference points

    Full Xin record →
  9. 09壬 Ren

    Yang Water · one of ten possible day-stem reference points

    Full Ren record →
  10. 10癸 Gui

    Yin Water · one of ten possible day-stem reference points

    Full Gui record →