Submit

Browse every extension by category.

All categories

Start from the job you need done.

All use cases

Starter kits for the way you work.

All professions

Extensions that upgrade the sites you already use.

All websites

Side-by-side verdicts and honest alternatives.

All comparisons

Free, single-page tools. No sign-up, most run right in your browser.

Chrome & browser
Privacy tests
Developer utilities
Images & media
Website inspector
Device checks
AI & productivity
All free tools

How-tos, safety explainers and data studies.

All guides
Submit an extension

↑↓ move · ↵ open · Tab filter · Esc close

Lumin PDF Chrome extension

Lumin PDF replaces Chrome's default PDF viewer with an editor that lets you sign, annotate, and merge documents in place, and adds AI-assisted reading tools like translation and summarization. It's best for people who regularly edit or sign PDFs online. The catch: it requests access to all sites and includes AI features that send content to third-party APIs.

  • PriceFreemium
  • CategoryProductivity
  • Works inChrome, Edge, Brave (desktop)

Last checked against the Chrome Web Store listing · Independent, not affiliated with Google

Add to Chrome See alternatives

Pros

  • combines viewing, editing, signing, and merging in one extension
  • integrates with Google account sign-in for saving and sharing
  • adds AI reading tools such as translate and summarize
  • replaces the default PDF viewer for a more capable editing experience

Cons

  • requests access to all URLs, not just PDF pages
  • AI features connect to external APIs to process document text
  • some advanced tools may require signing in with a Google account

Best for

  • editing and signing PDFs directly in the browser
  • merging PDF documents without extra software
  • quickly annotating or highlighting PDF content
  • using AI reading aids like translation or summaries on documents

Skip it if

  • users who don't want an extension running on every website
  • anyone wary of AI features that process document content externally

Key features

  • PDF viewing, editing, and annotation in the browser
  • electronic signing of PDF documents
  • merging and sharing PDF files
  • AI-assisted translation and summarization while reading

What Lumin PDF does

Lumin PDF takes over PDF viewing in Chrome and adds editing tools: you can annotate, sign, and merge documents without downloading separate software. It also layers in AI-assisted reading features, such as translation and summarization, for working through longer PDF content.

Lumin PDF free vs paid

Lumin PDF is free to install and use for viewing, basic editing, and sharing PDFs. As with similar tools, more advanced AI-assisted features may have separate usage considerations; check the extension's own settings for details on any limits.

Is Lumin PDF safe?

The extension requests access to all URLs plus Google account identity permissions, and it connects to external AI APIs (such as OpenAI and DeepSeek endpoints) for its reading-assist features. That means document content used with those features can be sent to third-party services, which is worth knowing before opening sensitive files.

Featured in

Guides featuring Lumin PDF

Lumin PDF: FAQs

Is Lumin PDF free?

Yes, Lumin PDF is free to install and covers core viewing, editing, and sharing of PDF documents.

Is Lumin PDF safe to use?

It requests broad access to all sites and connects to external AI APIs for reading-assist features, so avoid using those AI tools on sensitive documents you don't want processed externally.

How do I use the Lumin PDF extension?

Install it, open a PDF in Chrome, and use the toolbar to edit, sign, annotate, or merge the document.

Can I sign a PDF with Lumin?

Yes, electronic signing is one of Lumin PDF's core features.

What are Lumin PDF alternatives?

Xodo, SimplePDF, and Adobe Acrobat's extension are common alternatives with different feature mixes.

Does Lumin PDF replace Chrome's built-in PDF viewer?

Yes, once installed it opens PDFs in its own editor interface instead of Chrome's default viewer.

Can Lumin PDF translate or summarize documents?

Yes, it includes AI-assisted reading tools like translation and summarization, which send document text to external APIs to process.

Do I need a Google account to use Lumin PDF?

Basic viewing and editing may not require sign-in, but saving, sharing, and some sync features use Google account identity permissions.

Can Lumin PDF merge multiple files?

Yes, merging PDF documents is one of its listed capabilities.

Why does Lumin PDF request access to all websites?

It needs broad host permissions to detect PDF files across different sites and to run its content scripts for reading-assist features.