microsoft/Tokenizer

Typescript and .NET implementation of BPE tokenizer for OpenAI LLMs.

212

stars

93

commits

C#

primary language

Sep 10, 2026

updated

github.com/microsoft/Tokenizer/
ai
gpt
llm
openai
tokenizer

README

Tokenizer

This repo contains Typescript and C# implementation of byte pair encoding(BPE) tokenizer for OpenAI LLMs, it's based on open sourced rust implementation in the OpenAI tiktoken. Both implementation are valuable to run prompt tokenization in Nodejs and .NET environment before feeding prompt into a LLM.

Typescript implementation

Please follow README.

C# implementation

[!IMPORTANT] Users of Microsoft.DeepDev.TokenizerLib should migrate to Microsoft.ML.Tokenizers. The functionality in Microsoft.DeepDev.TokenizerLib has been added to Microsoft.ML.Tokenizers. Microsoft.ML.Tokenizers is a tokenizer library being developed by the .NET team and going forward, the central place for tokenizer development in .NET. By using Microsoft.ML.Tokenizers, you should see improved performance over existing tokenizer library implementations, including Microsoft.DeepDev.TokenizerLib. A stable release of Microsoft.ML.Tokenizers is expected alongside the .NET 9.0 release (November 2024). Instructions for migration can be found at https://github.com/dotnet/machinelearning/blob/main/docs/code/microsoft-ml-tokenizers-migration-guide.md.

Contributing

We welcome contributions. Please follow this guideline.

Trademarks

This project may contain trademarks or logos for projects, products, or services. Authorized use of Microsoft trademarks or logos is subject to and must follow Microsoft's Trademark & Brand Guidelines. Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship. Any use of third-party trademarks or logos are subject to those third-party's policies.

Contributors

shengyfu

40 commits

connor4312

15 commits

sbatten

12 commits

andreamah

8 commits

microsoft/Tokenizer

Typescript and .NET implementation of BPE tokenizer for OpenAI LLMs.

212

stars

93

commits

C#

primary language

Sep 10, 2026

updated

github.com/microsoft/Tokenizer/
ai
gpt
llm
openai
tokenizer

README

Tokenizer

This repo contains Typescript and C# implementation of byte pair encoding(BPE) tokenizer for OpenAI LLMs, it's based on open sourced rust implementation in the OpenAI tiktoken. Both implementation are valuable to run prompt tokenization in Nodejs and .NET environment before feeding prompt into a LLM.

Typescript implementation

Please follow README.

C# implementation

[!IMPORTANT] Users of Microsoft.DeepDev.TokenizerLib should migrate to Microsoft.ML.Tokenizers. The functionality in Microsoft.DeepDev.TokenizerLib has been added to Microsoft.ML.Tokenizers. Microsoft.ML.Tokenizers is a tokenizer library being developed by the .NET team and going forward, the central place for tokenizer development in .NET. By using Microsoft.ML.Tokenizers, you should see improved performance over existing tokenizer library implementations, including Microsoft.DeepDev.TokenizerLib. A stable release of Microsoft.ML.Tokenizers is expected alongside the .NET 9.0 release (November 2024). Instructions for migration can be found at https://github.com/dotnet/machinelearning/blob/main/docs/code/microsoft-ml-tokenizers-migration-guide.md.

Contributing

We welcome contributions. Please follow this guideline.

Trademarks

This project may contain trademarks or logos for projects, products, or services. Authorized use of Microsoft trademarks or logos is subject to and must follow Microsoft's Trademark & Brand Guidelines. Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship. Any use of third-party trademarks or logos are subject to those third-party's policies.

Contributors

shengyfu

40 commits

connor4312

15 commits

sbatten

12 commits

andreamah

8 commits

Languages

C#

43.9%

TypeScript

30.5%

Jupyter Notebook

24.2%

JavaScript

1.4%