BARK (Binär Automatisk Relä Kalkylator) was completed in February 1950 at a cost of 400.000 swedish kronor. BARK was a 32 bit machine and could complete an addition in 150 ms and a multiplication in 250 ms. It had a memory with 50 register s and 100 constants. It was later expanded to the double memory. BARK was built using standard phone relays.

BARK was developed by Matematikmaskinnämnen at the same time as BESK.