What Kind of Files Does Claude Allow You to Upload?

Claude, Anthropic's AI assistant, supports file uploads across several formats — but what you can send, how much of it you can send, and what Claude actually does with it varies depending on your plan, the interface you're using, and the type of file involved. Understanding the boundaries helps you work with the tool more effectively instead of running into silent failures or unexpected limitations.

The Core File Categories Claude Accepts

Claude can work with a reasonably broad range of file types, organized into a few functional categories:

📄 Documents and Text Files

The most commonly uploaded file types are text-based documents. Claude handles these well because its core strength is reading and reasoning about written content.

• PDF files — including multi-page reports, research papers, contracts, and manuals
• Plain text files (.txt) — clean and reliable for structured data, logs, or notes
• Microsoft Word documents (.docx) — for drafts, reports, and formatted writing
• Markdown files (.md) — useful for developers and technical writers
• CSV files — tabular data that Claude can read, summarize, or analyze row by row
• HTML files — Claude can parse the content within them

For PDFs specifically, Claude reads the text layer. Scanned PDFs that are image-only (with no embedded text) may not be readable unless OCR has already been applied to the document.

🖼️ Image Files

Claude's multimodal capabilities allow it to interpret images — not just acknowledge they exist, but actually describe, analyze, and answer questions about their content.

Supported image formats generally include:

This makes Claude useful for tasks like reading a screenshot of an error message, interpreting a chart or graph, reviewing a UI design, or describing what's visible in a photograph.

💻 Code Files

Developers frequently upload source code files for review, debugging, or explanation. Claude handles a wide range of programming languages when uploaded as raw text or code files, including .py, .js, .ts, .html, .css, .json, .xml, .yaml, and others. These are treated as text, so as long as the file is plaintext-encoded, Claude can read it.

What Claude Does Not Accept

There are file types Claude won't process, either due to technical limitations or safety considerations:

• Executable files (.exe, .dmg, .app, .sh scripts in some contexts) — Claude won't run or execute code
• Compressed archives (.zip, .rar, .tar.gz) — these generally can't be unpacked and read in the current interface
• Audio files — Claude doesn't process audio content like MP3s or WAV files
• Video files — video content is not supported for upload or analysis
• Binary or proprietary formats where the text layer isn't extractable — these may upload without error but return unusable results

Some file types may appear to upload successfully but produce no meaningful output. This is worth knowing in advance if you're working with less common formats.

Variables That Affect What You Can Upload

File support isn't one-size-fits-all. Several factors shape what's actually available to you:

Access tier. Free users and Claude Pro subscribers may have different upload allowances. Higher-tier plans generally support larger file sizes and more uploads per session.

Interface or API context. The Claude.ai web app has specific upload features built in. If you're accessing Claude through the API or a third-party application built on top of Anthropic's API, file handling depends on how that application is configured. Not every implementation enables file uploads.

File size limits. There are caps on how large an uploaded file can be. Very large PDFs, high-resolution images, or lengthy documents may hit size ceilings. These limits can change and vary by plan.

Number of files per conversation. Some contexts allow multiple file uploads in a single conversation; others may limit you to one at a time. The session context window — essentially how much information Claude can hold in memory at once — also plays a role when dealing with large documents.

Platform updates. Anthropic has been expanding multimodal and document capabilities over time. What's supported today may not reflect what was available six months ago, and the roadmap continues to evolve.

How Claude Handles Uploaded Files

It's worth being clear about what Claude is doing with your files. It's reading and reasoning about content — not storing files for future use, not running code, and not accessing embedded links or external resources referenced in a document. Each conversation is self-contained.

For PDFs and documents, Claude extracts the readable text and works from that. Formatting like headers, tables, and bullet points may or may not carry over cleanly depending on how the original document was structured.

For images, Claude uses vision processing to interpret visual content. This is useful for diagrams, charts, screenshots, and photos, but it's not flawless — complex tables rendered as images, handwritten text, or low-resolution files can produce less accurate results.

The Part That Depends on Your Situation

The file types Claude supports cover a meaningful range — documents, images, spreadsheets, code, and text-based formats. But whether those capabilities line up with your specific workflow depends on what you're trying to accomplish, which plan you're on, and whether you're using Claude directly or through a third-party tool that may handle uploads differently.

Someone reviewing contracts in PDF form has a very different experience than a developer uploading code files, a designer sharing wireframe screenshots, or an analyst working through CSV exports. The technical support may be the same on paper, but how useful it actually is comes down to the specifics of what you're uploading and what you need from it.