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日主 · the day stem as reference point

Day Master Calculator: Your Bazi Day Stem from a Birth Date

Today’s example at 26 Oct 2026, 10:03 CST (UTC+8) is a 癸酉 Yin Water Rooster day: the Day Master is Gui 癸 (Yin Water). At 23:00, this calculator advances the day and shows the midnight alternative.

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

Worked example · today, not your birth chart

Gui 癸: Yin Water Day Master

癸酉 Yin Water Rooster is the day pillar; its first character, 癸, is the Day Master.

Gui’s traditional description emphasises quietness, subtle movement and the ability to nourish through contact. Its Day Master image invites a reading of close observation, responsiveness and influence exercised in small increments. A useful reflection is how something understated becomes effective. The wider chart supplies the context for understanding where this Water is gathered, supported or drawn into activity.

Read Gui’s complete meaning and relationships →

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 →