The scales of Saranga are as follows :

Aarohanam (Ascending) : S P M2 P D N S’
Avarohanam (Descending) : S’ N3 D2 P M2 R2 G3 M1 R2 S

It is a janya raga, derived from Mechakalyani, which is the 65th raga on the Melakarta Scale (scale below)

65 Kalyani

Both prati madhyama (M2) and shuddha madhyama (M1) are used in Saranga, though the use of the latter is limited. Saranga has a soft and melodic feel, conveying a bhakti rasa as well as shringara and karuna rasas. In searching for an equivalents in the Hindustani ragas, I could not find an exact match. Hamir Kalyan can be considered an allied raga and Chaayanat also has similarities. Some well-known compositions in Saranga are Arunachala Natham and Varadarajam Upasmahe by Muthuswami Dikshithar, Nivada Ne Gana, Enta Bhagyamu and Mamava Raghurama by Tyagaraja, Gana Nathane by Periyasaami Thooran, Intamodi Seya (varnam) by Tiruvetriyur Tyagaraja and Jnana Sabhaiyil by Papanasam Sivan, to name a few.

Note : The 12 notes in the octave are named as below. Please note that C is used as Sa for the sake of simplicity as the scale is relative in Carnatic Music. Also note that the scales paint only a superficial picture of the raga as the gamakas(ornamentations) are a very important part of a raga.