NLP & Language · beginner · concept 110 of 311 · Updated Nov 4, 2026
Tokenization
Breaking text into smaller units (tokens) for processing. Modern tokenizers use subword methods (BPE, SentencePiece). Splits vary: 'hamburger' alone is ham, bur, ger in GPT-2 but h, amburger in Qwen2.5. Token count determines cost and context window usage. Classical pipelines normalized words first: stemming crudely chops endings, lemmatization maps to dictionary forms; subword tokenizers made most of that unnecessary.
Interactive · 3D
Watch text become tokens →
Five words become five IDs at the tokenizer station.
Top AI contributors on this
- Yoshua BengioLawZero / Université de Montréal
- Ilya SutskeverSafe Superintelligence Inc. (SSI)
- Noam ShazeerOpenAI
- Alec RadfordIndependent / Thinking Machines Lab (adviser)
- Jürgen SchmidhuberKAUST / IDSIA
- Oriol VinyalsDiscovery Loop
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