Are my files uploaded?

No. Files are read in the browser with the File API, and downloads are built with URL.createObjectURL. Nothing reaches a server.

Can I download every split part as a .zip?

No. The tool includes no compression library. Each part has its own download button, and Copy all takes the full set as text.

How does size splitting choose break points?

It fills each part up to the character target and breaks at paragraph boundaries where possible, so a part does not usually end mid-sentence.

Is the token count exact?

No. It estimates about four characters per token, which is close for English prose and less accurate for code. Leave headroom under a hard model limit.

Merge & Split Markdown Files

Two modes in one tool. Merge takes several .md files by file picker or drag-and-drop, lets you reorder them, and joins them with a horizontal rule, a filename heading, or nothing, then offers copy and download. Split takes one long document and breaks it at H1, at H2, or at an approximate character size, with a copy and download button per part and an estimated token count for AI context-window chunking. Files are read with the browser File API and never uploaded.

Merge many Markdown files into one, or split one long document into parts by heading or by size. Size splitting is useful for fitting a document into an AI context window or a RAG chunk. All file reading and every download happens in your browser with the File API. No file is uploaded to a server.

Drop .md files here, or pick them from disk.

Combined Markdown

Merge and split guides

Direct answers for combining Markdown files and breaking long documents into parts.

Combine .md FilesSelect several .md files, put them in the order you want, and join them with a horizontal rule or a filename heading between each one. Everything runs in the browser.Split by HeadingPaste one large Markdown document, choose H1 or H2 as the break point, and get one part per section with its own copy and download button.Chunk for AI ContextSplit a long document into size-limited parts so each chunk fits a model context window or a RAG index entry. Size is set in characters, with an approximate token count shown.Merge a Docs FolderSelect every file in a docs folder, order them, and join them into one document with filename headings so each source stays identifiable.Split Into ChaptersA manuscript that uses one H1 per chapter can be split into one file per chapter, each downloadable on its own.

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How to Use Merge & Split Markdown Files

Choose Merge or Split.
In Merge, add your .md files and order them with the up and down buttons.
Pick a separator, then copy or download the combined file.
In Split, paste or load one document and choose H1, H2, or size.
Copy or download each part; there is no zip download.

Frequently Asked Questions

Are my files uploaded?: No. Files are read in the browser with the File API, and downloads are built with URL.createObjectURL. Nothing reaches a server.
Can I download every split part as a .zip?: No. The tool includes no compression library. Each part has its own download button, and Copy all takes the full set as text.
How does size splitting choose break points?: It fills each part up to the character target and breaks at paragraph boundaries where possible, so a part does not usually end mid-sentence.
Is the token count exact?: No. It estimates about four characters per token, which is close for English prose and less accurate for code. Leave headroom under a hard model limit.

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About Merge & Split Markdown Files

Merge many Markdown files into one, or split one long document by heading or by size. Free, client-side, no upload. This tool runs entirely in your browser, so your content is not sent to a server. MarkdownMe provides free, fast, and reliable Markdown tools for developers, writers, and anyone who works with Markdown.