Claude: file upload limits and supported formats explained

Claude’s file handling capabilities have evolved significantly, allowing broader flexibility in managing documents, images, and structured data across both the chat interface and the API. Different limits apply depending on where files are used, the selected subscription tier, and whether you are working within projects, chat, or API pipelines.

Claude’s file size limits have expanded across chat and API.

Claude supports multiple workflows where files can be uploaded, but the limits differ between chat conversations, project knowledge bases, and API calls. Recent updates have raised the maximum sizes, providing better support for large datasets and rich media.

Context	Max Size Per File	Number of Files	Notes
Chat interface	30 MB	Up to 20 files per conversation	Applies across Free, Pro, Team, and Max plans
Inline images via API	8 MB	1 image per message	Increased from 5 MB after SDK v0.73 update
Image via URL in API	30 MB	Up to 10 URLs per request	Requires valid Content-Length from hosting server
Files API	5 GB	Up to 10,000 files per organization	Enterprise tenants can request 10 GB per file
Knowledge-base uploads	30 MB	Unlimited files	Files are indexed but subject to a 200,000-token retrieval limit

The most significant changes include raising the chat upload limit from 10 MB to 30 MB and expanding Files API capacity for enterprise accounts to handle up to 10 GB per file.

Claude now supports a broader range of file formats.

Claude processes a variety of documents, structured data, and images. Many formats are parsed natively, while others are converted automatically into a readable text representation for analysis.

Supported File Types	Details and Notes
Documents	PDF, DOCX, TXT, RTF, ODT, EPUB, HTML
Spreadsheets & Data	CSV, TSV, JSON
Presentations	PPTX (added August 2025)
Markdown	.md files fully supported
Images	JPEG, PNG, GIF, WEBP
Others	Certain compressed formats like .zip accepted if clean
Blocked types	Executables, scripts, and files failing malware scans

With the August 2025 updates, both PowerPoint presentations (.pptx) and Markdown files (.md) are now fully supported in chat and API contexts, making Claude more useful for technical documentation and reporting workflows.

Vision processing and token implications are more predictable.

While Claude accepts images for analysis, vision models convert these into tokens that count against the context window. On average, one standard image equals 4,000 to 6,000 tokens, depending on resolution and detail.

Image Resolution	Approximate Token Cost	Impact on Context Window
Small (<800×800 px)	~1,500–2,000 tokens	Minimal impact
Standard (1,200×1,200 px)	~4,000–6,000 tokens	Moderate impact
High-resolution (>3,000 px)	~8,000+ tokens	Can consume a significant portion of available context

Claude Sonnet and Opus variants support context windows up to 200,000 tokens, so multiple high-resolution images are manageable but still require planning for efficiency.

API and project integrations enable scalable workflows.

For developers and enterprise users, Claude’s API integrations have improved significantly. Larger payloads and more supported file types make it easier to build pipelines that handle documents, structured data, and images efficiently.

Key updates impacting API developers:

• Inline image uploads now support up to 8 MB per file.

• Larger datasets and archives can be processed via the Files API, up to 5 GB by default or 10 GB for enterprise.

• URL-based image fetching allows bypassing inline caps, as long as content headers comply with size and format rules.

Enterprise tenants benefit from an optional expanded storage tier with 100 GB of organization-wide file capacity.

Claude’s file handling capabilities are now fully optimized.

Claude now accommodates a wider range of use cases, from everyday document sharing to enterprise-scale dataset processing. By raising file size caps, expanding supported formats, and improving image handling within API and chat contexts, the platform has aligned its tools with professional workflows and more demanding enterprise environments. These updates provide greater flexibility for users who manage complex content across multiple channels.

____________

FOLLOW US FOR MORE.

DATA STUDIOS

datastudios.org