> ## Documentation Index
> Fetch the complete documentation index at: https://axiom.co/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Hash functions

> Learn how to use hash functions in APL.

Use hash functions to transform scalar values into fixed-length digests. They're useful for anonymizing personally identifiable information while preserving joinability, detecting duplicates, creating bucket keys for sampling, and verifying data integrity.

## List of functions

| Function                                                         | Description                                                    |
| ---------------------------------------------------------------- | -------------------------------------------------------------- |
| [hash](/apl/scalar-functions/hash-functions/hash)                | Returns a signed 64-bit integer hash of the input value.       |
| [hash\_md5](/apl/scalar-functions/hash-functions/hash-md5)       | Returns a 32-character MD5 hex digest of the input value.      |
| [hash\_sha1](/apl/scalar-functions/hash-functions/hash-sha1)     | Returns a 40-character SHA-1 hex digest of the input value.    |
| [hash\_sha256](/apl/scalar-functions/hash-functions/hash-sha256) | Returns a 64-character SHA-256 hex digest of the input value.  |
| [hash\_sha512](/apl/scalar-functions/hash-functions/hash-sha512) | Returns a 128-character SHA-512 hex digest of the input value. |