Twain Pro
The Markdown and MDX viewer is free, and stays free. Twain Pro is a one-time purchase that unlocks the editing and output features.
What is free
- Rendering Markdown and MDX, including GFM, footnotes, frontmatter, maths, diagrams, alerts, and MDX components
- All three view modes: rendered, raw source, and side by side
- Finder Quick Look previews
- Reading settings: appearance, the default theme, font, width, and text size
- Find in document, and the live table of contents
- Link checking: local links and images on every render, plus the opt-in remote check
- Show Changes against the last save or Git HEAD, and the one-click diff Twain offers when something else rewrites the document you have open
- The document diagnostics panel, including the opt-in remote link check
- Snippets and spelling, grammar and style are not separately licence-checked, but they live in edit mode, which is Pro; likewise searching a folder is free once a folder is open, and opening a folder is Pro.
What Pro unlocks
| Feature | Page |
|---|---|
| The editor (edit source, WYSIWYG, and save) | The editor |
| Version History: browsing revisions, comparing against one, and restoring | Show Changes and Version History |
| Review notes and Copy Report for Agent | Review notes |
| PDF and HTML export | HTML, Printing and PDF |
| Printing | Printing and PDF |
| Folder mode (open a folder, project tree, and folder search) | Working with a folder |
| The Sepia and High Contrast reading themes | Reading settings |
| Presentation mode | Presentation mode |
The trial
Twain includes a 7-day Pro trial that unlocks every Pro feature. Start it from the unlock prompt (shown when you first use a Pro feature) or from Twain ▸ Enter License…. The app menu and the Unlock Pro panel show how many days remain.
When the trial ends, the Pro features lock again, but the viewer keeps working. Reading, previewing, and the free review tooling are unaffected, indefinitely.
Buying and activating
Twain Pro is a one-time purchase, not a subscription. For current pricing, see twain.md.
Twain comes in two editions, and how you buy Pro depends on which one you run:
- Direct download (from twain.md) is licensed with a key. Buy Pro on the website, then enter the key in the app to unlock, as below. Activation is fully offline.
- Mac App Store will sell Pro as an in-app purchase, with no key to type: Buy Pro in the unlock panel, and Restore to re-activate on another Mac signed in to the same Apple Account. That edition has not been released yet.
If you bought Pro on the Mac App Store, you can unlock the direct edition for free. See Editions.
Entering a licence key
On the direct edition, to activate a licence you already have:
- Choose Twain ▸ Enter License….
- Paste your licence key (it begins with
TWAIN-) into the field. - Click Activate.
Once activated, the app menu shows Twain Pro — licensed to your email address.
Activation is offline
Licences are verified on your Mac against a key built into the app. There is no account to create and no server to ask for permission: verification works fully offline, and nothing a server says can switch Pro off. Your licence is stored in Twain's Application Support folder.
The direct edition does send an anonymous check-in at three moments: when it launches, when you start the trial, and when you activate a licence. It reports the app version; on launch, whether Twain is running free, on trial or licensed, and during a trial which day of the 7 you are on; and on activation, a one-way tag derived from the licence key, so we can see how many Macs a licence is used on. It never sends a device identifier, your OS version, your locale, your name, your email address, or anything about your documents, and nothing it receives back can affect your licence. Turn it off in Twain ▸ Settings ▸ Privacy. The Mac App Store edition sends no check-in at all, and has no Privacy tab.
Pro is bought from twain.md, which is also where Buy Pro in the direct download sends you. The Mac App Store in-app purchase is not available, because that edition has not been released yet. The 7-day trial unlocks every Pro feature meanwhile, and a licence key you already have activates normally.