Shadbala Calculator

Shadbala Worked Example: 23 August 1979, 23:53:18, Delhi

Before you enter anything, this is a real computed example: the birth moment AstroSage uses in its published sample report, so every number below can be checked against an independent table (see the verification section further down).

Strongest by Shadbala: Sun, 8.08 rupas against a minimum of 5 (ratio 1.61). Below their classical minimum: Mercury.

Chart for 23 August 1979, 23:53:18 (Asia/Kolkata). Lagna Taurus; night birth; weekday lord Jupiter, hora lord Venus, year lord Mercury, month lord Moon.

Shadbala totals in rupas

The six balas of each planet

What this Shadbala says

• Sun is the strongest planet by the ratio of its Shadbala to its minimum (1.61), and Mercury the weakest (0.94). The ratio, not the raw total, is what ranks planets: the minimums differ, so Mercury at 7 rupas and Saturn at 5 rupas are not being asked for the same thing.
• The lagna is Taurus, so Venus is the lagna lord — the planet most astrologers read first. It has 7.62 rupas against 5.5, meeting its minimum.
• Sun: 8.08 rupas (meets 5). Most of it is Sthana bala (236.81); its thinnest source is Dig bala (2.63). It sits in its moolatrikona sign.
• Venus: 7.62 rupas (meets 5.5). Most of it is Sthana bala (187.63); its thinnest source is Cheshta bala (0.61).
• Moon: 8.15 rupas (meets 6). Most of it is Sthana bala (220.06); its thinnest source is Cheshta bala (3.79).
• Mars: 6.72 rupas (meets 5). Most of it is Sthana bala (186.37); its thinnest source is Dig bala (14.05).
• Saturn: 6.42 rupas (meets 5). Most of it is Sthana bala (209.24); its thinnest source is Cheshta bala (3.85).
• Jupiter: 7.51 rupas (meets 6.5). Most of it is Sthana bala (218.96); its thinnest source is Cheshta bala (4.06). It is close to its exaltation point.
• Mercury: 6.63 rupas (below 7). Most of it is Sthana bala (176.30); its thinnest source is Naisargika bala (25.71).

Every Shadbala component

How Shadbala Is Calculated

Shadbala — literally six strengths — is the scheme Brihat Parashara Hora Shastra gives for measuring how able each of the seven visible planets is to deliver what it signifies. Each strength is counted in virupas (shashtiamsas); sixty virupas make one rupa. Rahu and Ketu have no Shadbala.

• Sthana bala (positional) — five parts: distance from the planet's debilitation point (uchcha, up to 60), its dignity across the seven vargas D1, D2, D3, D7, D9, D12 and D30 (saptavargaja: 45 in moolatrikona, 30 in own sign — 45 for own sign in the rasi chart, as AstroSage scores it — then 22.5 down to 1.875 by compound friendship), odd or even sign and navamsa (ojayugma, 15 each), angular house (kendradi: 60, 30 or 15) and decanate (drekkana, 15 when the planet's gender matches it).
• Dig bala (directional) — the arc from the point where the planet is powerless, divided by three: the Sun and Mars are strongest on the midheaven, the Moon and Venus at the nadir, Jupiter and Mercury rising, Saturn setting.
• Kala bala (temporal) — nine parts: day or night strength measured from apparent midnight (nathonnatha), the lunar fortnight (paksha), the thirds of day and night (tribhaga), the lords of the year, month, weekday and hour (abda 15, masa 30, vara 45, hora 60), declination (ayana, doubled for the Sun) and planetary war (yuddha).
• Cheshta bala (motional) — from the cheshta kendra, the arc between a planet's seeghrochcha and the mean of its mean and true positions; it peaks when a planet is retrograde. The Sun's is taken from its distance to the winter solstice point and the Moon's from its distance to the Sun.
• Naisargika bala (natural) — fixed: Sun 60, Moon 51.43, Venus 42.86, Jupiter 34.29, Mercury 25.71, Mars 17.14, Saturn 8.57.
• Drik bala (aspectual) — the aspects a planet receives, in virupas by the Parashari drishti table with the special aspects of Mars, Jupiter and Saturn: benefic aspects minus malefic ones, divided by four. The Moon's aspect is counted as benefic whatever its phase, as AstroSage counts it.

Minimum Shadbala Required for Each Planet

A planet is read as strong when its total reaches the minimum set for it. The minimums are unequal because the planets' natures are: Mercury has to reach 7 rupas, Saturn and Mars 5. The ratio of total to minimum is therefore the fair comparison between planets, and it is the rank the result prints.

Editions of the text differ on one figure: several give the Sun 6.5 rupas rather than 5. This calculator uses 5, the figure AstroSage prints, so a Sun between 5 and 6.5 rupas reads as meeting its minimum here and may not in a table that uses 6.5.

Shadbala Verification Against a Published Table

The worked example above is the birth AstroSage uses in its published sample Brihat Kundli (23 August 1979, 23:53:18, Delhi), and its Shadbala table is the reference this calculator was built against. Six of the seven totals agree within two virupas — three-hundredths of a rupa. Saturn's differs by about 15 virupas, all of it in saptavargaja, where the two calculations assign one divisional sign a different friendship. Every planet falls on the same side of its minimum in both tables.

Two conventions are deliberately not copied. AstroSage's printed Drekkana row reads 1 for every planet while its totals include the classical 15 or 0; the classical value is printed here. And in its second published sample AstroSage gives the hora bala of a Sunday birth 1 hour 45 minutes after sunrise to the Sun, where the hora table — including this site's own — gives that hour to Venus; this calculator follows the hora table.

Two of AstroSage's conventions are copied although they depart from the classical text, because AstroSage is the reference this site checks against: a planet in its own sign in the rasi chart scores 45 in saptavargaja, as in moolatrikona, where BPHS gives 30; and the Moon's aspect counts as benefic in drik bala even when the Moon is waning, where the paksha rule would class a Moon near the Sun as malefic. Each rests on AstroSage's second sample, where they bring Saturn's total to within one virupa of its table.

Reading a Shadbala Result

Read the ratio first, then the components. A planet well above its minimum can deliver its significations without strain; one below it tends to deliver them late, partly or with effort, and astrologers look to the dasha of a weak planet with more care. A strong planet carried mostly by Kala bala is strong by the time of birth rather than by its placement; one carried by Sthana bala is strong by sign and house, which is the more stable kind.

Shadbala measures capacity, not character. A strong malefic is strongly able to do what malefics do, and a weak benefic is a kindly planet with little room to act. That is why Shadbala is read beside the houses a planet rules and occupies, and beside its dasha, never on its own.

Limits of the Shadbala Calculator

Shadbala needs an exact birth time and place. Dig bala moves with the ascendant, which turns over about every two hours, and hora, tribhaga and nathonnatha change within the hour; a birth time wrong by twenty minutes can move a planet across its minimum. Planetary war (yuddha) is detected and flagged but not scored. And no strength table is a prediction: it is one classical input to a reading of the whole chart.

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