From wikipedia:
Tigers were capable of destroying the American Sherman or British Churchill IV at ranges exceeding 1,600 m. In contrast, the Soviet T-34 equipped with the 76.2 mm gun could not penetrate the Tiger frontally at any range, but could achieve a side penetration at approximately 500 m firing the BR-350P APCR ammunition. The T34-85's 85 mm gun could penetrate the Tiger from the side at over 1,000 m. The IS-2's 122 mm gun could destroy the Tiger at ranges exceeding 1,000 m from any aspect.
From a 30 degree angle of attack the M4 Sherman's 75 mm gun could not penetrate the Tiger frontally at any range, and needed to be within 100 m to achieve a side penetration against the 80mm upper hull superstructure. The British 17-pounder as used on the Sherman Firefly, firing its normal APCBC ammunition, could penetrate frontally out to over 2,000 m.