Shadbala means six strengths. Each of the seven planets, Sun to Saturn, is scored on its place in the chart, its direction, the time of birth, its motion, its natural strength and the aspects it receives. The scores are in virupas; 60 virupas make one rupa. The total is set against the figure the book gives for that planet. A planet that reaches it is counted strong, and one that exceeds it very strong.
☕ Six scores, one total
Shadbala asks how able a planet is to deliver what it signifies, and answers in six parts (Brihat Parashara Hora Shastra (Santhanam–Kapoor ed.), ch. 27, p. 264). Position (sthana) looks at the sign and varga placements. Direction (dig) looks at how near the planet is to its best angle. Time (kala) looks at the hour, the Moon's phase and the lords of the year, month, weekday and hora. Motion (cheshta) looks at the planet's speed and retrogression. Natural strength (naisargika) is fixed for each planet. Aspect (drik) adds the good aspects a planet receives and takes off the bad.
The parts are measured in virupas, sixtieths of a rupa. The six are added, and the total is read against the planet's required figure (Brihat Parashara Hora Shastra (Santhanam–Kapoor ed.), ch. 27, vv. 32–33, p. 287), in the card “Required totals” below. Mercury needs the most; Mars and Saturn the least.
The natural strengths rise in equal steps from Saturn to the Sun (Brihat Parashara Hora Shastra (Santhanam–Kapoor ed.), ch. 27, v. 14, p. 276): Saturn, Mars, Mercury, Jupiter, Venus, Moon, Sun; each figure is in “Natural strength of each planet” further down. They settle a tie between two planets of equal total.
Varahamihira gives five of these kinds, all but aspect, in a shorter form (Brihat Jataka, ch. II, vv. 19–21). Nava follows Parashara's measure, without the extra share the translator's note adds for the special aspects (Brihat Parashara Hora Shastra (Santhanam–Kapoor ed.), ch. 26, pp. 257–258), and shows each part, in rupas, on the horoscope page.
What each planet needs
- Sun: 390 virupas (6.5 rupas)
- Moon: 360 virupas (6 rupas)
- Mars: 300 virupas (5 rupas)
- Mercury: 420 virupas (7 rupas)
- Jupiter: 390 virupas (6.5 rupas)
- Venus: 330 virupas (5.5 rupas)
- Saturn: 300 virupas (5 rupas)
- Mix-up: shadbala covers Rahu and Ketu. It is for the seven planets, Sun to Saturn, only.
- Mix-up: a bigger total always means a stronger planet. Each planet has its own required figure; the total is read against it.
- Mix-up: shadbala tells whether a planet is good or bad. It measures how able the planet is; whether it is a benefic is a separate question.
Frequently asked questions
Where does Nava show shadbala?
On the horoscope page: each planet's six parts, labelled Position, Direction, Time, Motion, Natural and Aspect, its total in rupas and the total it needs.
What is a rupa?
A unit of strength equal to 60 virupas. The book's required figures are given in both.
Does shadbala change the daily panchang or Your Period?
No. In Nava it is shown on the horoscope page for study; it does not feed the day's score or Your Period.
Deep dive: natural strength and each part in turn
The table “Natural strength of each planet”, then where each of the six is explained, and what this builds on.
⚖️ Natural strength of each planet
| Planet | Natural strength |
|---|---|
| Saturn | 8.57 virupas |
| Mars | 17.14 virupas |
| Mercury | 25.71 virupas |
| Jupiter | 34.29 virupas |
| Venus | 42.86 virupas |
| Moon | 51.43 virupas |
| Sun | 60 virupas |
📐 The parts, one page each
Positional strength, time strength, motional strength and direction and natural strength each have their own page. The strength of a house, built on these, is on bhava bala.
🧭 What this builds on
Sign dignity, which the positional part scores, is on dignity and the share of results.