What is Gowri Panchangam?
Gowri Panchangam (Tamil Nalla Neram, "good time") is a South Indian system for finding auspicious times through the day. Like Choghadiya it needs only the sunrise, sunset and weekday — no birth chart. The day from sunrise to sunset is divided into 8 equal periods, and the night from sunset to the next sunrise into another 8.
The eight periods
Each period carries one of eight names with a fixed nature. Five are auspicious — Amirdham (Amrutha), Sugam, Uthi (Udyogam), Laabam (Labham) and Dhanam — and three are best avoided: Rogam, Soram (Soolam) and Visham. The weekday decides which period the day begins with, and the sequence then repeats through the eight slots; the night follows the same cycle four steps further along.
How the timings are set
Because the day and night are each split into eight equal parts, the length of a period depends on the day/night length at your place and date — longer in summer, shorter in winter. Set your location above so the times match your city.
Using Gowri Panchangam
Choose an auspicious (green) period for important work and read it alongside the day's Panchang, the Choghadiya and the inauspicious Rahu Kaal, Yamaganda and Gulika windows.