What Is The Maximum File Size Claude Can Upload? Limits, Formats, and Constraints

Uploading files is a central feature of advanced Claude workflows, powering research, automation, data analysis, and creative projects across a wide range of domains. The file upload process in Claude is governed by a set of interconnected technical boundaries, which include strict size limits, supported format lists, context window constraints, session-based rules, and storage policies that vary by interface and usage tier. The interplay of these boundaries shapes every stage of file handling, from initial submission to in-depth AI processing, and understanding their scope is crucial for users seeking reliability and scale.

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The maximum file size for Claude uploads is determined by the platform interface and user workflow.

The most immediate constraint for any user uploading a file into Claude is the per-file size limit, which is set at 30 megabytes in the chat, project, and web interfaces. Every file—whether it is a document, spreadsheet, image, or audio recording—must remain below this threshold for a successful upload. The system performs this check as soon as a file is selected, and files exceeding 30 megabytes are blocked with an error message, prompting the user to split or compress the content before trying again.

This limit is enforced for both free and paid accounts, across all geographies, and applies equally to files created within Claude, such as outputs from code tools or generated reports. No exceptions are made for organization size or tier. Within a single conversation or upload session, users may submit up to 20 files at once, each individually subject to the 30 megabyte cap. This enables multi-document and comparative analysis workflows, while maintaining system stability and user experience.

For developer and enterprise workflows using Claude’s Files API, the file size ceiling is significantly increased. The API permits uploads of up to 500 megabytes per file, with organizations allowed to store up to 100 gigabytes of files per workspace. This capacity supports research archives, large-scale analytics, and multi-stage projects that cannot be accommodated in the user interface. However, larger files present additional constraints that influence how much content can be actively processed by the AI in a given session.

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Claude File Size and Storage Limits Across Interfaces

Interface	Maximum File Size	Maximum Files per Session	Workspace Storage Cap
Chat/Project/Web	30 MB	20	Not specified
Files API (Developer)	500 MB	Not specified	100 GB per organization

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Supported file formats in Claude cover documents, structured data, images, and audio, with each type processed according to its properties.

Claude is engineered to handle a wide range of file formats. For documents, accepted types include PDF, DOCX, TXT, RTF, ODT, EPUB, and HTML. These formats are parsed for embedded text, structure, and, where applicable, basic formatting, enabling Claude to summarize, search, and transform written content. When a PDF is uploaded, the platform extracts text layers and metadata but may skip over embedded images or scanned content unless additional optical character recognition (OCR) tools are integrated.

Structured data files such as CSV and JSON are parsed for tables, field relationships, and schema, enabling Claude to process datasets for analytics, code generation, and transformation tasks. Spreadsheet files in XLSX format are also supported, though complex macros or formulae may not be interpreted in all workflows, and dense datasets may trigger context limits before file size is reached.

Image support includes JPEG, PNG, GIF, and WEBP formats. Uploaded images are used for referencing, description, and comparison tasks, but direct extraction of text from images through OCR is not available in all environments and may require separate tools. Image files must conform to the same 30 megabyte (or 500 megabyte via API) file size limits.

For audio, Claude supports MP3 and WAV formats. Uploaded audio files are primarily processed for transcription and content extraction within project knowledge bases. The file must still meet the per-upload size limit to be accepted.

Unsupported, encrypted, or corrupted file types are rejected immediately with a relevant error. This process is designed to ensure security, integrity, and consistency across Claude’s file handling ecosystem.

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Supported File Formats and Processing Details

File Type	Extensions	Primary Handling	Key Notes
Documents	PDF, DOCX, TXT, RTF, ODT, EPUB, HTML	Extracts and segments text	OCR may be required for scanned content; images often skipped
Structured Data	CSV, JSON, XLSX	Reads tables and fields	Large or nested datasets may trigger token limits
Images	JPEG, PNG, GIF, WEBP	Visual referencing	No default OCR; file size limits apply
Audio	MP3, WAV	Audio transcription	Only supported in some project environments

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Context window and token processing limits define how much of a file can be analyzed in a session.

No matter the original file size, Claude’s AI model processes uploaded content within a fixed context window, currently reaching about 200,000 tokens for advanced variants. This limit equates to hundreds of pages of text or substantial segments of a large dataset, but very large or dense files can still easily overflow this boundary. When this happens, only the content fitting within the window is available for analysis, summarization, or code generation at any given time.

Dense technical documents, long books, or spreadsheets with millions of rows may hit token ceilings long before reaching the file size maximum. Users must segment such files into manageable portions and use clear prompts, section references, or summaries to target specific content for each session. For API-driven ingestion of files near 500 megabytes, custom chunking and logic for incremental loading are essential to ensure comprehensive processing.

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Impact of Context Window and Token Limits on File Processing

File Characteristic	Token Demand	Typical Outcome
Short, sparse file	Low	Full file analyzed easily
Long, dense document	High	Only portion fits; must segment or summarize
Large dataset	Extremely high (nested tables)	Incremental analysis needed; token overflow common

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Upload session quantity, workspace policies, and output limits also affect file availability and workflow design.

The per-session file upload limit of 20 ensures that users can conduct rich, multi-source research or analytics in a single conversation, while preventing system overload. In project knowledge bases, there is no absolute cap on the number of files stored over time, but all must conform to per-file limits and will be subject to token constraints for retrieval.

For organizations using the Files API, the 100 gigabyte storage quota enables persistent multi-project collaboration, yet files that remain unused or unreferenced for long periods may be subject to automatic cleanup, archiving, or deletion under workspace policy. This requires teams to proactively manage data, document file relevance, and periodically review stored files to avoid accidental loss or compliance issues.

Any files created within Claude—including code tool outputs, reports, or transformed data—must also respect the upload size limits when downloaded or exported. If an output exceeds the applicable threshold, it cannot be delivered to the user, maintaining consistency and system stability.

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File Upload Quantity and Storage Policies Across Contexts

Context	Per-File Limit	Per-Session Upload Limit	Workspace Storage Limit	Retention Policy
Chat/Project UI	30 MB	20 files	Not specified	Manual or automated cleanup of unused files
Files API (Developer)	500 MB	Not specified	100 GB	Workspace policy, may delete unused files
Output File Generation	30 MB (UI) / 500 MB (API)	N/A	N/A	Same limits as uploads for all downloads

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Workflow best practices help users overcome file handling constraints and maximize Claude’s capabilities.

For consistent results, users should check file size and format prior to upload, breaking long documents or datasets into smaller, logically grouped segments when necessary. Adding section summaries, labels, or targeted prompts inside each upload enhances Claude’s ability to extract, summarize, or reference specific content efficiently, minimizing the risk of context overflow.

Developers managing large-scale or multi-file projects should automate chunking, file labeling, and state tracking to fit token windows and storage quotas. Proactive review and regular housekeeping of uploaded and stored files help avoid accidental loss due to retention policies and make large, persistent projects more manageable.

Monitoring upload feedback and staying current with Claude’s support documentation ensure that users can quickly adapt to changing file format compatibility and leverage new processing features as they are introduced. For complex analytics involving image OCR, dense data, or batch audio, integrating external tools or custom code logic extends the platform’s power.

By respecting Claude’s file size, format, context, and storage constraints, and planning workflows around them, individuals and teams can create scalable, efficient, and robust solutions for every aspect of document, data, and media-driven work.

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