12 volts, and however many mA's (milliamps) needed to drive however many led's you have/need.
say you have 47 LED's.
say each LED is 13mA.
it would be 13x47= 611.
you would need a power supply bigger than 611mA, or 0.6 amps. a 1000mA or 1 amp power supply would be more than sufficient.
say again you have 64 LED's
and each was 42mA
it would be 42x64 = 2688mA or 2.688 amps. (likely a 3000mA (3amp) supply)
find out how many mA your leds you ordered draw and then add it up.