Short answerOpenAI lists 50 MB per file and 50 MB total per request for file inputs. Anthropic's Files API lists 500 MB per file and 1 TB per organization, with content billed as input tokens.
| OpenAI file inputs | Anthropic Files API | |
|---|---|---|
| How | Send PDFs and other supported files by file ID, Base64 or URL in the Responses API | Upload once, then reference the file_id in document or image blocks |
| Limits | 50 MB per file and 50 MB total per request; Chat Completions accepts only PDFs | 500 MB per file, 1 TB per organization |
| Cost | Content counts as model input; no separate price shown on the guide | Upload, list and delete are free; content billed as input tokens |
| Scope | Per request | Visible to the whole workspace, not per end user |
Sending whole files every time is expensive for big libraries; retrieval over a vector store sends only relevant passages: OpenAI file search. See context windows.
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