Shadbala: Six-Fold Planetary Strength Calculation
Shadbala (literally "six strengths") is a comprehensive quantitative system described in Brihat Parashara Hora Shastra that measures how effectively each Graha can produce its intended results in a Kundli. It converts subjective planetary dignity into numerical values measured in Rupas and Shashtiamsas.
The Six Components
Sthana Bala (positional strength) evaluates a planet's sign placement, including exaltation, own sign, and debilitation status. Dig Bala (directional strength) assigns power based on house position — Jupiter and Mercury are strongest in the 1st house, Sun and Mars in the 10th, Moon and Venus in the 4th, Saturn in the 7th.
Temporal and Motional Strengths
Kala Bala (temporal strength) factors in day/night birth, planetary war, and hora rulership. Cheshta Bala (motional strength) measures a planet's speed — retrograde planets gain Cheshta Bala since they appear brighter and closer to Earth. Naisargika Bala (natural strength) is a fixed hierarchy: Sun is strongest, followed by Moon, Venus, Jupiter, Mercury, Mars, Saturn. Drig Bala (aspectual strength) accounts for benefic and malefic aspects.
Practical Application
A planet needs a minimum Shadbala score to deliver favorable results during its Dasha period. Planets exceeding the required threshold are considered strong and their significations — including any Yogas they form — manifest more prominently. AstroPath reports calculate Shadbala automatically to assess planetary potency.