Below is a table of comparative calendar years of Vikramasamvat and Śaka. it is based on the table of Slusser 1998: 390.

Some of the months may occur under alternative names, eg. Mārgaśīrṣa as Agahana.
Furthermore, a web based date converter can be found in the link below:
The Pancanga
Gregorian Year
Vikramasamvat
(begins 57 B.C.)
Nepalsamvat
(begins 20 October 879 A.D.)
Nepalasamvat Śaka Era
(begins 78 A.D.)
April-May
Vaiśākha (Vaisākha) -57


May-June
Jyeṣṭha (Jeṭha)

June-July
Āṣāḍha (Asāra)

July-August
Śrāvaṇa (Sāuna)

August-September
Bhādra (Bhadau)

September-October
Āśvina (Asoja)

October-November
Kārttika (Kārtika)
Kārttika (Kārtika) +879
+78
November-December
Mārgaśīrṣa (Maṅsira)
Mārgaśīrṣa (Maṅsira)
December-January Pauṣa (Pusa) Pauṣa (Pusa)
December-January
Pauṣa (Pusa)
-56
Pauṣa (Pusa) +880
+79
January-February
Māgha
Māgha
February-March
Phālguna (Phāguna)
Phālguna (Phāguna)
March-April
Caitra (Caita)
Caitra (Caita)
April-May


Vaiśākha (Vaisākha)
May-June
Jyeṣṭha (Jeṭha)
June-July
Āṣāḍha (Asāra)
July-August
Śrāvaṇa (Sāuna)