# Bun Read a file to a Uint8Array

> Read a file to a Uint8Array

- Skill: `jarle/bun-read-a-file-to-a-uint8array` (Agent Skill)
- Install (CLI): `npx skillmds@latest add jarle/bun-read-a-file-to-a-uint8array`
- Raw SKILL.md: https://api.skillmd.com/api/skills/jarle/bun-read-a-file-to-a-uint8array/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-read-a-file-to-a-uint8array

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# Read a file to a Uint8Array

The `Bun.file()` function accepts a path and returns a `BunFile` instance. The `BunFile` class extends `Blob` and allows you to lazily read the file in a variety of formats.

To read the file into a `Uint8Array` instance, retrieve the contents of the `BunFile` with `.bytes()`.

```ts  theme={"theme":{"light":"github-light","dark":"dracula"}}
const path = "/path/to/package.json";
const file = Bun.file(path);

const byteArray = await file.bytes();

byteArray[0]; // first byteArray
byteArray.length; // length of byteArray
```

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Refer to [API > Binary data > Typed arrays](/runtime/binary-data#typedarray) for more information on working with `Uint8Array` and other binary data formats in Bun.