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                *   [JSON Output Functions Parser](/v0.1/docs/modules/model_io/output_parsers/types/json_functions/)
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*   [Output Parser Types](/v0.1/docs/modules/model_io/output_parsers/types/)
*   Bytes output parser

On this page

Bytes output parser
===================

The `BytesOutputParser` takes language model output (either an entire response or as a stream) and converts it into binary data. This is particularly useful for streaming output to the frontend from a server.

This output parser can act as a transform stream and work with streamed response chunks from a model.

Usage[​](#usage "Direct link to Usage")
---------------------------------------

tip

See [this section for general instructions on installing integration packages](/v0.1/docs/get_started/installation/#installing-integration-packages).

*   npm
*   Yarn
*   pnpm

    npm install @langchain/openai

    yarn add @langchain/openai

    pnpm add @langchain/openai

    import { ChatOpenAI } from "@langchain/openai";import { BytesOutputParser } from "@langchain/core/output_parsers";import { RunnableSequence } from "@langchain/core/runnables";const chain = RunnableSequence.from([  new ChatOpenAI({ temperature: 0 }),  new BytesOutputParser(),]);const stream = await chain.stream("Hello there!");const decoder = new TextDecoder();for await (const chunk of stream) {  if (chunk) {    console.log(decoder.decode(chunk));  }}

#### API Reference:

*   [ChatOpenAI](https://api.js.langchain.com/classes/langchain_openai.ChatOpenAI.html) from `@langchain/openai`
*   [BytesOutputParser](https://api.js.langchain.com/classes/langchain_core_output_parsers.BytesOutputParser.html) from `@langchain/core/output_parsers`
*   [RunnableSequence](https://api.js.langchain.com/classes/langchain_core_runnables.RunnableSequence.html) from `@langchain/core/runnables`

* * *

#### Help us out by providing feedback on this documentation page:

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Combining output parsers

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