NEW
How Does Tokenizer Works
Watch: Most devs don't understand how LLM tokens work by Matt Pocock Tokenizers are the unsung heroes of modern AI and NLP systems, bridging the gap between raw human language and the numerical precision required by machine learning models. At their core, tokenizers convert text into structured, machine-readable units-tokens-enabling algorithms to process, analyze, and generate language at scale. Without them, models would struggle to handle the vast complexity and variability of natural language, from rare words to morphologically rich languages like Turkish or Bengali. Traditional word-based tokenization splits text on spaces or punctuation, but this approach creates two major issues: huge vocabularies and poor handling of rare words . For example, a naive tokenizer might assign an "unknown" label to 5% of words in a dataset, severely limiting model performance. Sub-word tokenizers like Byte-Pair Encoding (BPE) or SentencePiece solve this by breaking words into learned sub-units (e.g., "unhappy" → "un" + "happy"). These methods reduce the unknown-word problem to near zero while keeping vocabularies manageable (typically 16,000–50,000 tokens).