# ⏳ js-tiktoken tiktoken is a [BPE](https://en.wikipedia.org/wiki/Byte_pair_encoding) tokeniser for use with OpenAI's models. This is a pure JS port of the original tiktoken library. Install the library from NPM: ``` npm install js-tiktoken ``` ## Usage Basic usage follows, which includes all the OpenAI encoders and ranks: ```typescript import assert from "node:assert"; import { getEncoding, encodingForModel } from "js-tiktoken"; const enc = getEncoding("gpt2"); assert(enc.decode(enc.encode("hello world")) === "hello world"); ```