Folio

Folio is a PDF reader that lets users read, highlight, annotate, sign, and ask AI about documents.

Folio is a fast, clean PDF reader designed for Windows, macOS, and Linux. It allows users to open local files, PDF URLs, webpages, and Word documents, converting them into readable PDFs. Users can highlight text, add notes, draw freehand, insert text boxes, and apply handwritten signatures. The software includes an Ask AI feature that connects to existing ChatGPT or Claude subscriptions to answer questions about documents with clickable page citations. It saves reading states, highlights, and conversations locally while remaining free and open source.

Folio at a glance

Best for: Student, Researcher
Runs on: Windows, macOS, Linux, self-hosted, open source
Pricing: Free and open source
Released: October 2026
Category: AI productivity tool
Website: github.com/forward-future/folio

Key features

Open local PDFs, web links, webpages, and Word documents
Read with continuous scrolling, outlines, search, and focus mode
Highlight text, add notes, draw freehand, and insert text boxes
Capture and place handwritten signatures on documents
Ask AI questions about whole documents or specific passages
View high-resolution versions of images found in PDFs
Restore recent library, reading state, and window size

Use it for

Reading and annotating PDF documents and research papers
Converting Word documents and webpages into readable PDFs
Signing PDF forms with captured handwritten signatures
Asking AI questions about document contents using citations

Alternatives to Folio

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Surf — It combines local data storage with flexible AI model integration.
PDF Craft — It preserves formulas, tables, and document structure during conversion.
aiPDF — Chat with PDFs, web articles, YouTube videos, and podcasts in one place.
Benchpress — Evaluates document artificial intelligence models against specific user pages for accuracy, cost, and speed.
Marginalia — The file stays in the browser and every answer links directly to the cited passage.
ReadAny — It keeps your books and notes private using a local vector store and offline capability.
MinerU — Parses complex documents and tables into structured markdown for agents.
Libraire — Generates multiple summary styles, audiobooks, and video insights from text or PDFs.

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