The Arudha Lagna is the image of your Lagna: what the world sees rather than what you are. It is found by counting from the Lagna to the sign holding the Lagna lord and then counting the same distance on again from the lord. This calculator applies that rule to your chart and lists all twelve arudha padas, including the Upapada, the Jaimini marriage indicator.
The Arudha Lagna (AL, or A1) is the arudha pada of the 1st house. In Jaimini astrology every house has an arudha - its worldly projection - found by a simple counting rule applied to the house lord.
Here is the rule of the next four lines worked on one chart. If Aries rises and Mars, the lord of Aries, sits in Cancer, then Cancer is the 4th from Aries, and the 4th from Cancer is Libra. Libra is the 7th from Aries, which is one of the two cases the exception covers, so the BPHS rule moves the pada on to the 10th from Libra, which is Cancer. Read by the plain count with no displacement, the Arudha Lagna would have been Libra.
Where the Lagna shows your true self, the Arudha Lagna shows your maya - the reputation, status and image the world attaches to you. Planets sitting in or aspecting the AL colour how you are seen.
Every house has an arudha of its own, computed by the same projection from that house's lord, which is why the tool lists all twelve padas rather than the Arudha Lagna alone. Three carry names of their own because Jaimini technique leans on them: A7 the Darapada, A10 the Rajapada and A12 the Upapada. The sign of each pada is shown with the planets occupying it, since that is what a pada is read with.
The displacement rule is not agreed between the texts. BPHS ch. 29 vv. 1-3 name the twelve padas and vv. 4-5 displace a pada that lands in its own sign or in the 7th from it. Jaimini's Upadesha Sutras A1P1 su. 30 and 31 give a dedicated sutra to each of those two cases and let the plain count stand in both, and the Uttara Kalamrita agrees with Jaimini. On roughly one chart in three the two readings put a pada in different signs.
The sign in the table on this page is the BPHS pada, because the rest of the tool's Jaimini rules are BPHS's. The engine computes the plain Jaimini sign as well and never averages the two, since there is no third reading either text would recognise; the side-by-side view of both schools is on the Jaimini tab of the full kundli result. You can also read the Jaimini answer straight off the rule above: it is the sign the plain count reaches before the vv. 4-5 displacement is applied.
The Lagna represents your true self and reality, while the Arudha Lagna is its worldly reflection - the image and status the world assigns to you. The gap between the two shows how much perception differs from who you actually are.
Find the sign holding the Lagna lord, count the distance from the Lagna to that lord, then project the same distance forward from the lord. If the result lands on the Lagna or the 7th from it, the 10th house is used instead.
Arudha padas (A1-A12) are the projected images of each house, showing how its matters appear to the outside world. This tool lists all twelve, including the Arudha Lagna (A1) and the Upapada (A12), the primary Jaimini marriage indicator.
Two do, and they disagree. BPHS ch. 29 vv. 1-3 name the twelve padas and vv. 4-5 displace a pada that falls in its own sign or in the 7th from it. Jaimini's Upadesha Sutras A1P1 su. 30-31 apply no displacement in either case, and the Uttara Kalamrita follows Jaimini. The sign shown in the table here is the BPHS pada; the two schools are printed side by side on the Jaimini tab of the full kundli result.
The Upapada (UL) is the arudha of the 12th house and the primary marriage indicator in Jaimini astrology. It is listed here with the other eleven padas, and the sign given for it is the BPHS pada, computed with the ch. 29 vv. 4-5 displacement. Because that displacement fires on two of the twelve possible lord placements, the Upapada is one of the padas where the schools most often part company, and the full kundli result's Jaimini tab shows both readings together.
Comprehensive multi-chapter analysis: charts, all dashas, strengths, yogas, doshas, life areas, longevity & remedies.
For educational purposes. Astrological interpretations are traditional and not a substitute for professional advice.