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Free creator tool

Document to Markdown Converter

Converted on your device. No file is ever uploaded.

No document handy?

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Postonus Pro

Loved this tool? Stop copying and pasting to schedule.

Connect 14+ channels (including Bluesky, Threads, and Reddit) in one dashboard. Schedule your content once, let Postonus auto-repurpose it native to every network.

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No card until you publish.

Why people use it

  • Your file never leaves the machine it is on. The converter is a WebAssembly build running inside your own tab — there is no upload step, so there is no copy of your document on anyone else’s disk. Most online converters work by receiving your file first.
  • Drop up to 20 files and walk away. Each one converts in turn, keeps its own result, and can be copied on its own or downloaded together as a ZIP.
  • Structure survives the trip: heading levels, tables (including merged cells), numbered and nested lists, task-list checkboxes, footnotes and endnotes, block quotes, and the speaker notes hiding behind presentation slides.
  • It reads the file, not the file name. A spreadsheet someone saved with a .doc extension still converts, because the format is identified from the content itself.

How it goes

  1. 01

    Drop your documents

    PDF, Word, PowerPoint, Excel, OpenDocument, Rich Text, EPUB, or CSV. The converter downloads itself the first time you reach the drop zone, then stays cached.

  2. 02

    Read the result

    Each file gets a rendered preview and the raw Markdown behind it. Anything that could not be read says exactly why — a password, a missing part, or a PDF that turned out to be scanned images.

  3. 03

    Copy or download

    Copy the Markdown, save a single .md file, or take the whole batch as a ZIP. Word, PowerPoint, and OpenDocument files also offer their embedded images as a separate download.

About this tool

Convert documents to Markdown without uploading them anywhere

A browser-based document to Markdown converter for PDF, Word, PowerPoint, Excel, OpenDocument, RTF, EPUB, and CSV. Batch up to 20 files, keep tables and footnotes intact, and send nothing to a server.

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Questions

Frequently asked questions Everything the first evaluation usually needs.

What if I'm already on Buffer / Pallyy / Publer?

Keep them. Run Postonus side-by-side for 30 days. Put your 3 best posts into a Growth Workflow. If it isn't earning its keep, cancel us — not them.

Does the AI write my posts?

No. You write the post. Postonus's AI re-fits your draft into each platform's native shape — character limits, tone, hashtag norms. You review every variant before it publishes. Voice profile keeps it sounding like you.

Which platforms do you support?

Fourteen: Instagram, TikTok, YouTube, LinkedIn, Facebook, X, Threads, Pinterest, Bluesky, Reddit, Telegram, Discord, Google Business Profile, and Tumblr. WhatsApp Groups support is in beta.

How does the free workspace and the 14-day trial work?

Sign up with no card and you get a free workspace: up to 3 connected channels, unlimited writing, and dated drafts on the calendar. Scheduling and publishing need a card. Adding one starts a 14-day trial on the plan you pick — nothing is charged until day 15, and your drafts are already there waiting.

Can I import from another tool?

Yes. Bulk CSV import handles up to 50 posts per file (multiple files OK). Direct-from-Buffer import is on the Q4 roadmap.

What happens if a post fails to publish?

Workers retry with exponential backoff. Failures show up in the Activity Feed with one-click retry. We email you only for unrecoverable failures (e.g. revoked token).