Compressed stride tables in a multi-bit Trie structure perform lookups. An input lookup key is divided into strides including a current stride of S bits. A valid entry in a current stride table is located by compressing the S bits, forming a compressed index of D bits into the current stride table. A compression function logically combines the S bits to generate the D compressed index bits. An entry in a prior-level table points to the current stride table and has an opcode field indicating which compression function and mask to use. Compression functions can include counts of leading-repeated bits, and very complex functions such as hashes, CRC, encryption. A function table stores results of the complex functions that are addressed by the S bits of the current stride. The opcode field in the stride entry selects from among several tables, each storing results for a different function.