# Fast Document Reader

> AI writes it. You're the one reading it.

Plans, specs, summaries, transcripts, the Word doc a client sent — reading them has quietly become
most of the job. Fast Document Reader is built for those hours: a fast, light Mac reader for **Markdown,
Word (`.docx`), OpenDocument (`.odt`) and plain text**, opened the instant you click. It's easy to
look at and never bogs your Mac down, however many files you leave open. It reads first and gets out
of the way — and when a line in your own Markdown is wrong, you fix it where you are, a block at a
time, saved when you say so.

Free · Mac (Apple silicon, macOS 13+) · open source (MIT) · coming to the Mac App Store · by
DubDubDub Corp.

## It's a text file. Why is your fan on?

Because most document and Markdown apps are a web browser wearing a costume. That's the beat before
the window opens, the memory that climbs the longer you leave it running, and yes — the fan, over
some text. This one is a Mac app, plain and simple. Every number below was measured, not marketed.

| | Fast Document Reader |
|---|---|
| Opening | Instant. There's no loading screen, because there's nothing to load. |
| While you read | Uses no processor time at all. The fan stays off; your battery doesn't notice it's open. |
| Memory | ~127 MB with nine large documents open at once — and ~52 MB handed back the moment you close them. It doesn't creep up over the day. |
| Big files | A 4,000-paragraph document opens right away, and the scrollbar tells the truth about its length from the first frame. |
| Diagrams | Flowcharts and sequence diagrams appear right in the page, even with no internet. Drawn once, instant every time after. |
| Images | Scroll past a picture and it quietly gives its memory back; scroll up and it's there. The page never jumps while you read. |
| Code | Colored the way your editor colors it, with a Copy button on every block. |
| Reading | Tabs, find (⌘F), bigger or smaller text (⌘+/⌘−), automatic dark mode. |
| Editing | Right-click a block, or press E to edit · I to add below · U/J to move · D to delete. Your changes are yours until ⌘S. |
| Finding your place | T opens a list of every heading. Click one and the cursor goes there, ready to edit that section. |
| Editing big files | Only the block you changed is redrawn — 9 ms on a 64,000-character file, 29 ms on 1.2 MB. Undo stays instant. |
| Word & OpenDocument | Opens `.docx` · `.docm` · `.dotx` · `.dotm` · `.odt` — **read-only**, shown as the author formatted it: headings, tables whose columns line up, images and equations even inside a cell, footnotes, comments, tracked changes and right-to-left text. Want to change one? One click hands it to your editor of choice. |
| Extract for an AI | `--extract` turns a `.docx` or `.odt` into **clean Markdown** from the command line — headless, so an AI reads it without spending its budget parsing the file. |
| Plain text | Opens .txt · .csv · .log too, shown exactly as written. Files from Windows or Linux arrive readable — saved back in the encoding they came in. |
| Works on | Macs with Apple silicon (M1 and later), macOS 13 or later. |
| Price | Free — and the source is public, so every number here is something you can check yourself. |

## What it looks like

- **Diagrams show up, even offline.** Flowcharts and sequence diagrams appear right where they
  belong — on a plane, on the subway, anywhere. Each one is drawn a single time, then it's instant
  forever, and it stays sharp however far you zoom in.
- **Pictures, without the weight.** Images look sharp, but the ones you've scrolled past quietly
  hand their memory back. Your place on the page never shifts while you're reading.
- **Code you can actually read.** Code is colored the way your editor colors it, on its own card,
  with a Copy button on every block and a switch for long lines. Thirty-four languages, under the
  names you actually type — `yml`, `golang`, `c++`, `sh`, `tsx`.
- **Formulas, drawn once.** Maths between `$$` renders with no internet, and stays sharp however far
  you zoom in — same as the diagrams.
- **A map of the document.** Press `T` for every heading in a sidebar. Click one and the reading
  cursor goes there — so the next keystroke edits that section, rather than just looking at it.
- **The Word doc, as authored.** `.docx` (and `.docm`/`.dotx`/`.dotm`) and OpenDocument `.odt` open
  read-only, faithful to the document's own styling — tables whose columns actually line up, images
  and equations even inside a table cell, footnotes, comments and tracked changes. Your reading-size
  preference multiplies on top of what the author set, the way Word's own zoom does. To change one,
  a single click hands it to your editor of choice.
- **A Word file, ready for an AI.** Point an AI at a `.docx` and it burns tokens just parsing the
  file. `--extract` prints it as clean Markdown instead — the same engine the reader uses, so what
  the AI reads matches what you see. One command, no window.
- **Plain text, exactly as written.** `.txt`, `.csv` and `.log` open here too, shown as they are,
  with nothing reinterpreted as formatting. A Korean file written on Windows arrives readable
  instead of as rows of question marks, and is saved back the way it came.

## What's actually inside

Pure Swift, AppKit and TextKit — no Chromium, no Electron, no web runtime for the text. Diagrams are
mermaid and formulas are KaTeX, both bundled in the app and snapshotted once to a vector PDF cached
by content hash — so `$$…$$` and flowcharts alike render with no internet and stay sharp at any zoom.
Code is colored by a single left-to-right scanner across thirty-four languages, which is why a URL
inside a string never turns the rest of the line into a comment. Off-screen media drop their pixels
while keeping their exact layout size, so nothing reflows and the scroll bar never swings. The whole
document is laid out up front — that is what makes the scroll bar honest from the first frame — while
an edit re-renders only the block it touched, which is why undo stays instant in a file where other
apps stall. Text files are read as the encoding they were written in and written back the same way,
so a document made on Windows doesn't quietly become something else.

## Install

Coming to the Mac App Store, where it'll be free and one click. Until then, build it from source:

```bash
git clone https://github.com/ww-w-ai/fast-document-reader
cd fast-document-reader
./Scripts/make-app.sh
open FastDocReader.app
```

## Support
- Report a bug or request a feature: https://github.com/ww-w-ai/fast-document-reader/issues
- Email: biz@ww-w.ai
- Privacy policy: https://ww-w.ai/fast-document-reader/privacy/

## Links
- Source code: https://github.com/ww-w-ai/fast-document-reader
- Publisher: https://ww-w.ai (DubDubDub Corp.)