In BaZi, your four natal pillars describe what you are — but the luck pillars (大运, Da Yun) describe when. Every ten years you enter a new pillar whose stem and branch interact with your natal chart, coloring that decade of your life: some decades support your Day Master, others challenge it.
This calculator derives your Da Yun the classical way, not with a generic table. The direction follows the Yuan Hai Zi Ping rule — yang-year males and yin-year females walk the pillars forward, the reverse walk backward — and your starting age is converted from the days between your birth and the nearest solar term, three days counting as one year.
You get the exact starting date of your luck, all eight ten-year pillars with their Gregorian year ranges and traditional ages, the pillar you are walking right now highlighted, plus the coming Liu Nian (流年) annual pillars — the year-by-year layer practitioners read against the current decade.
The chart data is completely free, no account needed. When you want to know what your current Da Yun actually means for career, wealth and relationships, an AI BaZi reading is one click away.