# Feature Hashing

> Source: https://sukruyusufkaya.com/en/glossary/feature-hashing
> Updated: 2026-05-13T20:02:15.680Z
> Type: glossary
> Category: veri-bilimi-ve-veri-yonetimi
**TLDR:** A method that maps features into a fixed-dimensional space using hash functions to provide scalable representation.

<p>Feature hashing is used to control representation cost in very high-dimensional or open-ended categorical spaces. Each category or token is mapped into a fixed-dimensional vector space using a hash function. This is especially efficient in text data, advertising systems, and large-scale logistics datasets. Its drawback is that different inputs can collide into the same hashed location. Even so, it remains a widely used engineering solution in high-scale systems.</p>