There are 30 tithis in each lunar month, named as follows:

Krsna paksa Gaura paksa (dark fortnight) (bright fortnight) 1 Pratipat 1 Pratipat 2 Dvitiya 2 Dvitiya 3 Trtiya 3 Trtiya 4 Caturthi 4 Caturthi 5 Pancami 5 Pancami 6 Sasti 6 Sasti 7 Saptami 7 Saptami 8 Astami 8 Astami 9 Navami 9 Navami 10 Dasami 10 Dasami 11 Ekadasi 11 Ekadasi 12 Dvadasi 12 Dvadasi 13 Trayodasi 13 Trayodasi 14 Caturdasi 14 Caturdasi 15 Amavasya (new moon) 15 Purnima (full moon)Ekadasi, the eleventh day of each lunar fortnight, has special religious significance in Hinduism and Jainism—usually observed by fasting.