Claude file upload limit: 500 MB a file in a chat, 30 MB in a Project, 10 MB an image

Which Claude upload limit did you hit?

The message on screen tells you which cap stopped the upload. Claude has six of them, and Anthropic publishes the wording for only two. Here is each wall and the fix that works in the next minute, from Anthropic's help center and API docs as of October 2026.

Byte size is rarely the real wall. 500 MB of plain text is far more than any Claude model can read at once, and Anthropic's own Files API docs list "Exceeds context window size" as a separate error for exactly that case. In the app, the same problem shows up as the length limit message. Page count and image size are the two caps people hit first.

How big a file can you upload to Claude?

A chat takes files up to 500 MB, and that's the largest cap Claude has. It covers documents only. A Project file stops at 30 MB. An image stops at 10 MB on claude.ai, a limit that sits on Anthropic's vision page and not on the upload page most guides quote.

Claude accepts ten document types: PDF, DOCX, CSV, TXT, HTML, ODT, RTF, EPUB, JSON and XLSX. Excel needs one setting first. Anthropic's upload page says "You must enable code execution and file creation in your account to upload XLSX files." Images can be JPEG, PNG, GIF or WebP. An animated GIF is read from its first frame only.

Pixels have two limits, not one. An image can be up to 8000x8000 pixels. But Claude doesn't look at it at that size. The vision docs say the newest models downscale anything longer than 2,576 pixels on its long edge, and older ones anything past 1,568. So a 4K screenshot is read at about two thirds of its width. Anthropic's tip runs the other way too: use images of at least 1000x1000 pixels, because small ones read badly.

How many files can you upload to Claude?

You can attach up to 20 files to one chat, per Anthropic's upload page. The vision docs give images the same number, counted per message: "20 per message on claude.ai". A Project has no file count. It's capped by content, which has to fit in Claude's context window.

Anthropic publishes no daily or hourly upload count, on any plan. That's the main difference from ChatGPT. Uploads draw on your usage limit instead. Anthropic's usage page lists "File attachment size" among the factors that use it up. A 300 page PDF in every message spends your five hour allowance far faster than a one line question does. When that runs out you'll see the session limit message, and what to do when Claude says usage limit reached covers it.

One habit saves the most usage. Put a document you'll ask about more than once in a Project. Anthropic says Project files are cached, and "cached portions count less against your limits than new content". The cache expires after a break, so the first message after it counts the files in full again.

Does Claude read charts and images inside a PDF?

Claude reads the charts, images and graphics in a PDF only when the file has 100 pages or fewer. From page 101 to 1,000 it reads the text and skips every visual. Past 1,000 pages it refuses the file. Anthropic's words: "For PDFs from 101 to 1000 pages, Claude processes text only and doesn't analyze visual elements."

Other document types get even less. For DOCX, ODT, RTF, EPUB and the rest, Claude extracts text only, so a chart pasted into a Word file is invisible. If the chart matters, save that page as a PDF of its own, or take a screenshot and attach it as an image. When you ask about a page, give the number your PDF viewer shows, not the one printed on the paper. Anthropic's help page makes that point.

The API docs explain why visuals cost more. Each PDF page becomes an image plus its extracted text, and the text alone runs 1,500 to 3,000 tokens a page. That's why a long report fills a context window faster than its file size suggests. For a document that's too long for one pass, how to summarize a PDF with AI gives the section by section method.

What are Claude's Project knowledge limits?

A Project takes files of up to 30 MB each, with no limit on how many, as long as the total fits in Claude's context window. On a paid plan, Claude switches the Project to retrieval (RAG) as it nears that limit. Anthropic says that "expand[s] your project's capacity by up to 10x". Free accounts get up to 5 Projects and no retrieval mode, per the Claude pricing page and the RAG help article.

The window itself depends on the model. On paid plans, the newest Claude Opus, Sonnet and Haiku models read 1 million tokens in a chat as of October 2026, and older ones 200,000 to 500,000. Anthropic puts 200,000 tokens at "about 500 pages of text or more". Project files also lose their pictures. The upload page lists Project content as "Text extraction only (except for multimodal PDFs)". What is a context window explains how the window fills.

What does "exceeds the length limit" mean in Claude?

It means the message you're about to send, files included, won't fit in what's left of the chat's context window. The error help page gives the full wording: "Your message will exceed the length limit for this chat. Try attaching fewer or smaller files or starting a new conversation." It isn't a byte cap. A small text file can trigger it at the end of a long chat.

Most paid users rarely see it now. On paid plans with code execution turned on, Claude summarizes earlier messages as a chat nears its limit and keeps the full history. Anthropic says the error still appears "when sending a very large first message". The fix is to send less: one chapter, the pages your question needs, or the text pasted in place of a file with many images.

What are the Claude API file limits?

The API caps each uploaded file at 500 MB, the same as a chat, with 1 TB of storage per organization, per Anthropic's Files API docs. A Messages API request is capped at 32 MB in total. It can carry up to 600 PDF pages, or 100 when the request's context window is under 1 million tokens. Images are capped at 10 MB each, 5 MB on Amazon Bedrock and Google Cloud.

The API takes more images than the app: 100 per request on models with a 200,000 token window and 600 on the rest. Past 20 images in one request, a stricter size rule applies to every image. Anthropic's advice is to keep each one at 2000 pixels or less on both sides. An oversized file returns error 413, "File too large", and an organization that has used its 1 TB gets a 400.

How do Claude's upload limits compare with ChatGPT and Gemini?

Claude ties ChatGPT on file size and beats Gemini's 100 MB, but its 30 MB Project cap is far below either. ChatGPT is the only one that publishes an upload count. We read each vendor's own help page in October 2026, and OpenAI's through an archive.org copy of 18 September 2026, because help.openai.com refuses automated reads.

The ChatGPT row comes from OpenAI's File Uploads FAQ, and the full breakdown is in the ChatGPT file upload limit by plan. The Gemini row comes from Google's upload help page and its limits page. Google names a rolling file limit in its "You've reached your limit for chats with files" message, but it publishes no number for it.

Whizi, which publishes this page, is the last row, and it loses on size. Its 100 MB website cap is a fifth of Claude's, and a message carries at most 100,000 characters of extracted text, far less than a 1 million token Claude window. Attachments also need a paid plan. Where it helps is the day Claude's usage limit runs out: Claude models answer there on a separate meter, and uploading a file costs no credits. Every Whizi cap and its error is in why a file upload failed.