Calmly Writer Online
calmlywriter.com
A blank page with a focus mode that dims everything but this sentence
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stackedit.io
A Markdown editor with live preview that keeps working offline.
Split-pane Markdown editing with synchronised scrolling, KaTeX maths, Mermaid diagrams and a generated table of contents, all running in the browser with documents in local storage. It can sync to Google Drive, Dropbox or GitHub, and publish straight to a blog, if you want it to. The interface is dense and the project moves slowly, but it has outlived a dozen prettier rivals.
AltFTool does this too
If you would rather not leave the site, Markdown Preview covers the same job here — free, no account, and it runs in your browser.
Open Markdown PreviewQuestions
Works the moment the page loads. No account, no email, no trial. Documents sit in browser storage by default, so clearing site data without a linked cloud account loses them.
No. StackEdit does the work inside your browser, so the file never leaves your device — you can load the page, disconnect from the network, and it still works. That makes it a reasonable choice for material containing personal data.
Documents sit in browser storage by default, so clearing site data without a linked cloud account loses them.
Alternatives
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calmlywriter.com
A blank page with a focus mode that dims everything but this sentence
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