> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/web/compare-files/compare.md).

# Compare PDF File Differences with JavaScript

Compare PDF files effortlessly with the Apryse SDK. Visually analyze differences in images, text, forms, and more. Start overlaying and pixel-by-pixel comparison now! The Apryse Web SDK streamlines se

{% hint style="info" %}
**Requirements**

*These packages are required to use these features in production. Trial keys have unlimited access to all features*

<a href="https://apryse.com/capabilities#Compare" class="button primary">Package: Compare</a>
{% endhint %}

Comparing files provides the ability to understand what has changed from one file to another.

With the Apryse SDK, you can visually compare the differences between 2 files (images, paths, text, forms, shadings, and other types of content).

## Demos

[Semantic Text Compare Demo](https://showcase.apryse.com/semantic-text-compare) [Compare by Image Overlay Demo](https://showcase.apryse.com/compare-files)

## Get started

[PDF Overlay](/web/compare-files/diffing.md) To provide a visual document comparison by [overlaying](https://en.wikipedia.org/wiki/Blend_modes#Overlay) and [masking](https://en.wikipedia.org/wiki/Mask_\(computing\)).

[Pixel-by-pixel (Image Overlay)](/web/compare-files/pixels.md) To provide a visual document comparison by gathering each pixel to find the [sum of absolute differences](https://en.wikipedia.org/wiki/Sum_of_absolute_differences).

[Semantic Text](/web/compare-files/semantic.md) To detect differences between two docuemnts on a word-by-word basis.


---

# Agent Instructions
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## Querying This Documentation
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Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.apryse.com/web/compare-files/compare.md?ask=<question>&goal=<endgoal>
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