A project keeps chats, files, and instructions on one topic in a single place. For work that runs over a long time, it saves you from re-uploading materials and re-explaining every time. This guide covers only what OpenAI's docs describe. Screen names can change, so compare with what you see.
What a project is
OpenAI's docs describe a project as a unit that holds related chats, files, instructions, and sources in one place. There are two kinds. A ChatGPT project holds files you upload and materials you connect. A local project connects a folder on your computer so chats can use it.
The docs' rule of thumb is simple. Make a project when the work runs over time, or when several outputs depend on the same files and materials. A one-off task can just start as a chat.
Creating and using one
The docs describe this for the ChatGPT desktop app. In the app's Projects screen, ChatGPT projects and local projects are listed together. I could not confirm this time whether the web or mobile screens look the same.
- Create a project and fill in its instructions and sources.
- Start a new chat inside that project. It then uses the project's shared files and instructions. A chat you start also shows up in the Chats list.
- Use one chat per deliverable. That is what the docs recommend. Mixing several goals in one chat blurs the context.
- To attach more folders to a local project, choose Edit project, then Add folder, from the project menu. To change the default working folder, select the folder and click "Set as default."
Sources, instructions, and local folders
In a ChatGPT project, files and connected materials go in the Sources area. The docs say, in effect, that a ChatGPT project cannot directly access folders on your computer. Materials on your computer have to be uploaded or connected.
Project instructions apply to every chat in that project. They suit rules you want fixed inside the project, such as "always answer in a formal tone" or "use Markdown for tables."
A local project lets ChatGPT read and change files in the folders you connect. The docs say so directly, so be careful about which folder you attach. Syncing a chat does not upload your whole local folder, and the sandbox settings decide what local commands can read, change, and reach over the network.
Limits, and how it differs from memory and custom instructions
Memory plays a different role. OpenAI's docs describe memory as a way to bring useful context from earlier chats into later work, and advise keeping rules that must be followed in a separate document rather than in memory. That guidance is written in the Codex context. I could not confirm how projects and memory affect each other in regular ChatGPT chats.
Custom instructions are personal preferences that apply to all chats. Project instructions are rules that apply only inside that project. The scope is what differs.
- The docs do not list numeric limits such as file count or size, so this guide does not give numbers either.
- Remote projects currently support only one folder.
- Even if you attach several folders, only the default folder is where AGENTS.md, skills, and config.toml are discovered automatically. The other folders can still be searched, read, and edited.
- Pinning only changes where a project appears in the sidebar. It does not change what it can access.
- A task does not switch from local to cloud execution partway through. When your computer is unavailable, an eligible task may continue in a cloud container, but that container cannot access your local files.
Real examples
You are preparing to move and want to ask questions for a month while referring to a lease, quotes, and a schedule.
Create a project called "Moving prep" and upload the quotes and schedule as sources. Instructions: "Show amounts in dollars and dates as month/day." Then, in a new chat: "Make a comparison table of the three quotes."
It answers with the project's sources and instructions already applied, so you do not re-upload the files for each chat. You still need to check the table against the originals. For documents with a lot of personal information, it is safer to redact them before uploading.
You want to run a repeated task against a documents folder on your computer.
Create a local project, connect that folder, and set it as the default working folder.
ChatGPT can read and change the files in the connected folder. That is why it is a good idea to back up important originals before putting them in the folder.
Common mistakes and when not to use it
- Do not pile everything into one project. Using a separate chat for each deliverable is what the docs recommend.
- In a local project, ChatGPT can change files in the folder you connect. Do not attach an important folder without a backup of the originals.
- Do not upload files containing Social Security numbers, bank account numbers, passwords, or similar information as sources.
- AGENTS.md and skills are not discovered automatically in folders other than the default folder.
- Do not mistake pinning for an access setting. It only changes the sidebar position.
FAQ
How many files, and how large, can I put in a project?
The docs I checked this time give no numbers. Check the notes on your own screen.
How is a project different from a regular chat?
A chat started in a project uses the project's shared files and instructions. A regular chat has no such shared context.
Does it work on a free account?
Availability by plan is not covered in the docs I checked this time, so I cannot answer that.
Checked against the official docs on 2026-10-30. Sources: Projects in ChatGPT and Codex, Memories (ChatGPT and Codex), Personalization. How we write