ChatGPT Projects Upload Limits: Files, Sources, and Chats

ChatGPT Projects have several distinct limits that work independently: a limit on how many files a project can hold, a limit on individual file size, a rolling limit on how much you can upload in a given period, and the context window each chat can use within the project. Understanding which limit you have hit is the first step to working around it.

For concise project context that travels to any assistant without needing repeated uploads, tools like fenbs keep decisions, rules and current tasks outside any single platform. A connected assistant reads them at the start of each session.

File count and size limits

Each project can hold a limited number of files. Each individual file also has a maximum size. These limits are set by OpenAI and apply per project, not per account. Uploading a file that would push a project over either limit typically fails with an error message, though the message does not always distinguish between the two.

For the current limits, check OpenAI's help center↗ (opens in a new tab). These numbers change with plan updates and are OpenAI's to communicate, not ours to state. Knowing which limit applies tells you whether the fix is to remove an existing file to make room or to reduce the file you are trying to add.

Rolling upload quotas

Separate from the per-project file count, there is a rolling quota on how much you can upload across all projects within a window of time. If you hit this limit, you cannot upload to any project until the window resets, even if individual projects have room.

This limit catches people who upload many large files across a busy work period. The fix is to wait for the window to reset, to remove files you no longer need or to reduce the size of what you are uploading. Converting a large PDF to a text extract before uploading often reduces size significantly without losing the content the assistant needs.

Which plans include Projects

ChatGPT Projects are not available on the free plan. Paid plans that include Projects have higher upload quotas than the base limits. OpenAI's plan page explains which plans include Projects and what limits apply to each. Check their current plan details rather than relying on any summary, as plan terms change.

The question of whether the free plan has unlimited uploads is a different issue from Projects specifically. Free users have a message limit and cannot use Projects. For file uploads outside Projects, such as single files attached to a conversation, check OpenAI's current free plan terms.

How many chats can a project have

There is no documented hard limit on the number of conversations inside a project. In practice, having many chats in one project makes finding earlier conversations difficult, and it does not help the assistant find relevant context: each new chat reads the project files and instructions, not the history of previous chats.

Keep projects lean by archiving or deleting chats that are no longer useful. A project with twenty conversations about different topics is harder to navigate than separate projects organized by topic.

Chat context within a project

Each chat has a context window: the total amount of text the assistant can hold in its working memory at once. In a project, this includes the project files, the custom instructions and the conversation so far. A long conversation with many large files can hit this limit even when the project itself is within its file count and size limits.

When a chat reaches its context limit, the assistant may start ignoring older parts of the conversation or produce less coherent responses. Starting a new chat inside the same project resets the context window while keeping access to the project files and instructions.

Working within the limits

Keep files focused. If a 200-page report contains three pages that are relevant, extract those pages and upload the extract rather than the full document. The assistant reads what you give it; a focused extract gives more reliable answers than a large file it must search.

Review project files periodically and remove those you no longer use. Old drafts, superseded plans and reference material that is no longer relevant count against your quota without adding value.

For troubleshooting a specific upload failure, see ChatGPT project unable to upload a file. For comparing how ChatGPT and Claude handle project sources, Claude Projects vs ChatGPT Projects covers the main differences.

How to do this with fenbs

1. Create a free account and add a project in fenbs for your ongoing work.
2. Record the context that would otherwise be uploaded repeatedly, such as project rules, approved decisions and current tasks, as structured records in fenbs.
3. Connect your AI assistant from Integrations. It reads the fenbs context at session start without using a project file slot.
4. Keep ChatGPT project files for primary source documents that need full text search: research papers, contracts, reference specifications.
5. Add source links and document references to fenbs Links and listings so any assistant can find them without a re-upload.