Markdown Editor
Block-based pages or plain Markdown · saved in this browser
A free Markdown editor that saves as you type
Write in rich text with slash commands or in raw Markdown: drag-and-drop blocks, toggles, callouts, tables, images, KaTeX math and Mermaid diagrams, with nested pages, favourites, Trash and page history. Link notes with [[wikilinks]], tag them, and export any page as Markdown, HTML or PDF. No sign-up: everything stays in this browser.
Key facts
- Pages save as you type in this browser (localStorage, with images and page history in IndexedDB). Nothing is uploaded and there’s no account.
How this works: Checked against 4 worked examples,
How this works
How it’s tested
4 worked examples for this page are checked by automated tests before every release: given the inputs, the tool must show the expected answer.
Privacy
You choose. Stays on your device unless you click to send something to a service you pick; the tool says which. Your documents stay in this browser. If you added your own AI key, the AI sends the text you pick to that provider. Cover photos load from Unsplash. About privacy labels
Changes
- A short tour on your first visit shows the / menu, your pages and import. Show me around in the ⋯ menu plays it again.
- Imports a Notion export (Markdown & CSV) in the browser: pick the pages, and its sub-pages, links, images, callouts and databases come in, with a list of what didn’t.
- Added a database block: a table with typed columns, sorting, search, a tag filter, totals and CSV import and export, saved as a plain Markdown table.
- When AI runs on your own key, each run shows what it cost, and a costly one asks before it is sent.
- Pictures in your pages now save in Safari private tabs too.
- The AI helpers can now use your own OpenAI, Anthropic, Gemini or OpenRouter key, set in Settings.
- Added AI helpers that summarise, rewrite, proofread and translate with the browser’s built-in model (desktop Chrome), so your text never leaves the device.
- Fixed the cover picker and a paste security flaw; print and HTML export strip scripts from imported files, and a failed save now says so and keeps your text.
Frequently Asked Questions
Where are my documents saved?
In this browser only (localStorage, with images and page history in IndexedDB). Nothing is uploaded, so your notes stay private, but they don’t follow you to another device or browser, and clearing site data deletes them. To keep a copy or move to another device, use Backup & sync (binarydecimal.com/backup, linked in the footer): one file with every page and image, plus your other tools’ data. Export → All pages (.zip) also works for the pages alone.
Can I write plain Markdown instead of rich text?
Yes. Switch from Rich text to Markdown at the top to edit the raw Markdown, with Write, Split (side by side with a live preview) and Preview views. Both modes edit the same page, and Copy as Markdown or Download .md always gives you standard Markdown.
How do I link notes together?
Type [[ and pick a note to create a wikilink. Clicking a link to a note that doesn’t exist yet creates it. Backlinks and the graph view (under More) show which notes point to the one you’re reading.
I’ve used Notion. Will this feel familiar?
If you’ve used Notion or another block editor, most of it will. Type / for blocks (to-dos, toggles, callouts, tables, images, equations, columns, sub-pages), drag ⋮⋮ to move blocks, select text to format it, nest pages in the sidebar, star favourites, search everything with ⌘K, restore old versions from page history and recover deleted pages from Trash. It all runs in your browser, with no account.
Can I bring my pages over from Notion?
Yes. In Notion, export your workspace or a page as “Markdown & CSV”, then choose More → Import here and pick the zip (or all its Part zips at once). The editor reads it in your browser, shows the pages to pick from, and brings in sub-pages, links between pages, images, callouts, toggles, code, math and databases as tables with typed columns. Nothing is uploaded. Afterwards it lists what didn’t come across, such as links to pages outside the export or files other than images.
How do I turn a note into a PDF?
Open Export → Print / Save as PDF and pick “Save as PDF” as the printer. You can also download the note as an HTML file and open it in any browser.
Pairs well with
Notion, Obsidian and Typora are trademarks of their respective owners. Binary Decimal is not affiliated with or endorsed by them.