A three-pane Markdown editor, with an optional on-device AI assistant
Write Markdown with colour syntax highlighting and a live-rendered preview side by side, drag and drop images straight into your text, then export to standalone HTML, PDF or native .md - all fully offline. When you want a hand, an optional on-device AI assistant can summarise a document or rewrite a passage, entirely on your own computer.
Document list, colour-highlighted Markdown source, and a live-rendered preview - all visible at once, so you always see exactly what you're writing next to exactly how it will look.
Summarise a whole document with one click, or select a passage and rewrite it against your own instruction. Runs a small local language model entirely on your own computer - nothing about your document is sent anywhere, and it's always optional.
Headings, bold/italic, code, links, blockquotes and task lists are all coloured as you type in the source pane, so the raw Markdown itself is easy to scan - not just the rendered preview.
Drop an image straight into the editor and it's embedded in your Markdown automatically - no separate upload step, no broken relative paths to manage.
Find & replace across a document, plus a floating quick-format menu that appears on text selection for bold, italic, links and headings without reaching for the keyboard.
One click to a standalone HTML file, a PDF via your system print dialog, or a native .md file - so a document written here drops straight into a repo, an email, or wherever it needs to go next.
Right-click any document to open, duplicate, export or delete it without leaving the list - or import an existing .md file straight in and it appears alongside the rest.
Export your whole document set to a single JSON backup file, and import it back on another device whenever you like - nothing is ever locked in.
Every document lives only in this app on your device via local storage. The optional AI assistant runs entirely on your own computer too - nothing you write is ever sent anywhere.
Most people either write Markdown in a general-purpose text editor with no preview, or use a browser-based Markdown tool that needs a connection and sends your text to a server. Here's how a dedicated offline editor compares.
| Feature | Markdown Editor | A general text editor | A browser-based Markdown tool |
|---|---|---|---|
| Pricing model | Free | Varies | Often free, sometimes subscription |
| Live-rendered preview alongside the source | ✓ | ✕ | ✓ |
| Colour syntax highlighting for Markdown | ✓ | ✕ (unless configured) | ✓ |
| One-click export to HTML, PDF and .md | ✓ | ✕ | Varies |
| Works fully offline, nothing sent to a server | ✓ (AI assist included) | ✓ | ✕ (needs a connection) |
General comparison as of August 2026.
A Markdown syntax guide - source and live preview side by side
A recipe card, rendered cleanly from plain Markdown
Summarise with Metre2 AI - generated entirely on your own device
No - use it straight from your browser, on a phone, tablet or PC, with no sign-up. It works offline once it has loaded, and you can add it to your home screen or desktop like an app. There is also a Windows desktop version in the Microsoft Store if you prefer an installed app.
No. The browser edition needs no account at all. The Windows app uses the same shared Metre2 account as Vector, Forma and every other Keystone app - sign in once and it works everywhere.
No. Writing, formatting, exporting and the document list all work fully offline - your documents live on your own device. The optional on-device AI assistant also runs entirely on your own computer once its model has loaded, so nothing about your writing is sent anywhere.
Summarise a whole document, or rewrite a selected passage against your own instruction (tighten it, make it more formal, fix the tone, and so on). It runs a small local language model on your own computer - nothing about your document is sent anywhere, and it's entirely optional.
Headings, bold/italic/strikethrough, inline code and fenced code blocks, links and images, blockquotes, ordered and unordered lists, task lists, and GitHub-flavoured tables - all rendered live in the preview pane as you type.
Standalone HTML, PDF (via your system print dialog), or native .md files - plus a full JSON backup of every document for safekeeping or moving to another device.
No, it's a free app.
No. Every document stays on your device via local storage. If you use the optional AI assistant, it runs entirely on your own computer - your text is never sent to a server.