German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-433 had a displacement of 769t when at the surface and 871t while submerged. She had a total length of 67.1m (220.1feet), a pressure hull length of 50.5m (165.7feet), a beam of 6.2m (20.3feet), a height of 9.6m (31.5feet), and a draught of 4.74m (15.55feet). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of NaNPS for use while surfaced, two AEG GU 460/8–27 double-acting electric motors producing a total of 750PS for use while submerged. She had two shafts and two 1.23abbr=onNaNabbr=on propellers. The boat was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at . U-433 was fitted with five 53.30NaN0 torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.82NaN2 SK C/35 naval gun, 220 rounds, and a 2sp=usNaNsp=us C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
The boat's career began with training at 3rd U-boat Flotilla on 24 May 1941, and continuing with active service on 1 August 1941 as part of the 3rd Flotilla for the remainder of her service.
In two patrols she damaged one merchant ship, for a total of .
U-433 took part in two wolfpacks, namely:
U-433 was sunk on 16 November 1941 in the Mediterranean E of Gibraltar, in position 36.2167°N -46°W, by depth charges and gunfire from Royal Navy corvette . There were 6 dead and 38 survivors.