Numerology works with numbers derived from your birth date and name. It's symbolic, intuitive, and relatively simple to learn.
Tarot is a divination tool using archetypal images. It's responsive to the present moment and the reader's intuition.
BaZi is a complex, rule-based system with centuries of documented theory. It doesn't rely on intuition for the core calculation — the chart is mathematically derived. Interpretation involves skill, but the framework is rigorous and falsifiable.
The main difference: Tarot and numerology can answer present-moment questions well. BaZi excels at long-term life mapping — understanding your entire life architecture and timing. Tarot tells you about today's weather; BaZi tells you about the climate and seasons of your life.