A browser editor is most useful when it shows you exactly what your markup becomes without running anything. A sanitized preview and a local-only document give you that, with no upload and no script execution.
01Edit and preview, never execute
Markdown and HTML are rendered to a small, explicit subset and sanitized before they are shown.
Scripts, event handlers and dangerous URLs are removed, and external resources are never loaded.
Pasted JavaScript is kept for reference only — it is never executed.
02Keep the document in your own browser
Autosave is off by default. When you enable it, the document is stored only in your browser, and Clear or Reset removes it. Nothing is uploaded and no account is required.
Frequently asked questions
Does the preview run my code?
No. The preview is sanitized and rendered in a sandboxed frame; scripts and event handlers are removed and never execute.
Is my document uploaded?
No. The document stays in your browser, and autosave is opt-in and stored only on your device.
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