Defined in tensorflow/python/ops/

See the guide: Strings > Hashing

Converts each string in the input Tensor to its hash mod by a number of buckets.

The hash function is deterministic on the content of the string within the process. The hash function is a keyed hash function, where attribute key defines the key of the hash function. key is an array of 2 elements.

A strong hash is important when inputs may be malicious, e.g. URLs with additional components. Adversaries could try to make their inputs hash to the same bucket for a denial-of-service attack or to skew the results. A strong hash prevents this by making it difficult, if not infeasible, to compute inputs that hash to the same bucket. This comes at a cost of roughly 4x higher compute time than tf.string_to_hash_bucket_fast.


  • input: A Tensor of type string. The strings to assign a hash bucket.
  • num_buckets: An int that is >= 1. The number of buckets.
  • key: A list of ints. The key for the keyed hash function passed as a list of two uint64 elements.
  • name: A name for the operation (optional).


A Tensor of type int64.