---
title: "Engine"
description: "The local PDF engine underneath the ready-made viewer and every headless integration."
source: "https://www.embedpdf.com/docs/engine"
---

# EmbedPDF Engine

The Engine is the asynchronous PDF boundary shared by every EmbedPDF
integration. It owns document I/O and PDF operations; Viewer and Headless add
plugins, reactive state, and UI on top.

Use `@embedpdf/engine` directly when you need to open, inspect, transform, or
save documents without adopting a viewer UI.

## What the Engine provides

- **Document lifecycle** — open bytes, work through a typed document handle,
  then close the document and destroy the engine.
- **Page operations** — inspect page geometry and order, render pages, rotate,
  move, insert, extract, and delete pages.
- **Document features** — text and search, metadata, forms, annotations,
  attachments, security, and downloads.
- **Local execution** — PDFium runs through WebAssembly in a Web Worker, away
  from the browser's main thread.

## Where it fits

The ready-made Viewer and Headless Components both depend on the same Engine
contract. Choose those layers when you need UI; use the Engine directly for
background processing, custom rendering pipelines, or non-UI workflows.

```sh
pnpm add @embedpdf/engine
```

[Create your first local engine](https://www.embedpdf.com/docs/engine/getting-started).