# Read a file to an ArrayBuffer (/docs/guides/read-file/arraybuffer)

<!-- agent-signals: reading_time_min: 1 · est_tokens: 198 · updated: 2026-07-28 -->
Related: [Read a file to a Buffer](/docs/guides/read-file/buffer.md), [Check if a file exists](/docs/guides/read-file/exists.md), [Read a JSON file](/docs/guides/read-file/json.md), [Get the MIME type of a file](/docs/guides/read-file/mime.md), [Read a file as a ReadableStream](/docs/guides/read-file/stream.md), [Read a file as a string](/docs/guides/read-file/string.md)

The `Bun.file()` function accepts a path and returns a `BunFile` instance. `BunFile` extends `Blob`, so you can read the file lazily in a variety of formats. Use `.arrayBuffer()` to read the file as an `ArrayBuffer`.

```ts index.ts icon="/icons/typescript.svg"
const path = "/path/to/package.json";
const file = Bun.file(path);

const buffer = await file.arrayBuffer();
```

***

Read the binary content of the `ArrayBuffer` with a typed array, such as `Int8Array`. For `Uint8Array`, use [`.bytes()`](/guides/read-file/uint8array).

```ts index.ts icon="/icons/typescript.svg"
const buffer = await file.arrayBuffer();
const bytes = new Int8Array(buffer);

bytes[0];
bytes.length;
```

***

See [Typed arrays](/runtime/binary-data#typedarray) for more on working with typed arrays in Bun.