# Bun Convert a Buffer to a ReadableStream

> Convert a Buffer to a ReadableStream

- Skill: `jarle/bun-convert-a-buffer-to-a-readablestream` (Agent Skill)
- Install (CLI): `npx skillmds@latest add jarle/bun-convert-a-buffer-to-a-readablestream`
- Raw SKILL.md: https://api.skillmd.com/api/skills/jarle/bun-convert-a-buffer-to-a-readablestream/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: jarle (https://skillmd.com/u/jarle)
- Updated: 2026-09-21
- Page: https://skillmd.com/skills/jarle/bun-convert-a-buffer-to-a-readablestream

---


# Convert a Buffer to a ReadableStream

The naive approach to creating a [`ReadableStream`](https://developer.mozilla.org/en-US/docs/Web/API/ReadableStream) from a [`Buffer`](https://nodejs.org/api/buffer.html) is to use the `ReadableStream` constructor and enqueue the entire array as a single chunk. For a large buffer, this may be undesirable as this approach does not "streaming" the data in smaller chunks.

```ts  theme={"theme":{"light":"github-light","dark":"dracula"}}
const buf = Buffer.from("hello world");
const stream = new ReadableStream({
  start(controller) {
    controller.enqueue(buf);
    controller.close();
  },
});
```

***

To stream the data in smaller chunks, first create a `Blob` instance from the `Buffer`. Then use the [`Blob.stream()`](https://developer.mozilla.org/en-US/docs/Web/API/Blob/stream) method to create a `ReadableStream` that streams the data in chunks of a specified size.

```ts  theme={"theme":{"light":"github-light","dark":"dracula"}}
const buf = Buffer.from("hello world");
const blob = new Blob([buf]);
const stream = blob.stream();
```

***

The chunk size can be set by passing a number to the `.stream()` method.

```ts  theme={"theme":{"light":"github-light","dark":"dracula"}}
const buf = Buffer.from("hello world");
const blob = new Blob([buf]);

// set chunk size of 1024 bytes
const stream = blob.stream(1024);
```

***

See [Docs > API > Binary Data](/runtime/binary-data#conversion) for complete documentation on manipulating binary data with Bun.