Mahadasha calculation of vedic astrology by pharashira maharshi based Nakstras. First navkam we can follow to understand it.  Mahadasha Online Calculator based on date of birth as per vedic astrology, N.C. Lahari ayanamsa will follow to generate up to 5 levels of dasha period. Dasha, Bhukti, Bhukthi, Antara, Sukshma, Pran dashas & give you dasha prediction. Dasha period will be calculated based on moon star irrespective of lagna.

Star Star Lord Dasha Period Percentage
Ashwini Kethu 7 7/120*100 =
Bharani Venus 20 20/120*100=
Krithika Sun 6
Rohini Moon 10
Mrigasir Mars 7
Arudra Rahu 18
Punarvasu Jupiter 16
Pushyami Saturn 19
Ashlesha Mercury 17
120 Years 100 %

Based on above calculation with percentage we can do any levels of dasha period.

Dasha > Bhukthi > Anthara > Sukshma > Prana > Avi Prana > Viprana etc.