Let’s Build the GPT Tokenizer: A Complete Guide to Tokenization in LLMs

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Build a complete guide to tokenization in LLMs based on Andrej Karpathy's video

intermediate Published 15 Oct 2025
Action Steps
  1. Watch Andrej Karpathy's 2h13m tokenizer video
  2. Read the translated book chapter on tokenization
  3. Implement key pieces of code from the chapter
  4. Experiment with different tokenization techniques for LLMs
Who Needs to Know This

NLP engineers and researchers on a team can benefit from understanding tokenization in LLMs to improve model performance and efficiency. This knowledge can also be useful for AI engineers and ML researchers working with language models.

Key Insight

💡 Tokenization is a key component of how LLMs work

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📚 Build your own GPT tokenizer with this complete guide!
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