ChatGPT projects, Claude projects, and custom GPTs explained
Custom GPTs are going away: OpenAI says they retire on December 11, 2026, personal accounts can no longer create them, and existing ones can be migrated to plugins. Google is doing the same with Gems on personal accounts, which become skills. Projects, which keep chats, files, and instructions together in one place, remain in ChatGPT, Claude, and Perplexity as of November 10, 2026.
Projects and custom assistants in ChatGPT, Claude, and Gemini
If your team set up a custom GPT or a Gem to answer the same questions every week, it has a deadline. This page is part of using AI for everyday tasks and explains, from the companies’ help pages as of November 10, 2026, what projects, custom GPTs, Gems, and skills are, and what OpenAI’s custom GPT retirement FAQ and Google’s equivalent change for you.
In short, projects stay and personal assistants turn into skills. A project is a workspace: chats, files, and instructions kept together, so you don’t paste the same background into every conversation. A custom GPT or a Gem was a version of the assistant with its own instructions and files; both are being replaced by skills, which are folders of instructions the assistant loads when a task calls for them.
Projects, GPTs, and skills: what each is for
OpenAI describes the difference in two words: a GPT is “single player,” a fixed set of instructions and files that you publish, while a shared project is “multi-player,” a team workspace that changes as people add to it. Anthropic puts it another way: a project gives background knowledge that is always loaded, while a skill is a procedure that Claude applies only when it is needed, in any chat.
Use a project for ongoing work with its own documents, such as a client account or a quarterly report. Use a skill for a method you repeat everywhere, such as your house style for proposals.
ChatGPT projects and Claude projects side by side
| ChatGPT projects | Claude projects | |
|---|---|---|
| Free plan | Yes, 5 files per project | Yes, up to 5 projects |
| Files | 25 per project on Go and Plus, 40 on Pro, Business, and Enterprise; 10 per upload | 30 MB per file, as many as fit in Claude’s context; paid plans switch to retrieval near the limit |
| Instructions | Apply only in the project and override your global custom instructions | Apply to every chat in the project |
| Sharing | Every plan, with chat or edit access; up to 5 collaborators on Free, 10 on Go and Plus, 100 on Pro | Team and Enterprise only, with “Can view” or “Can edit” |
| Memory | Default or project-only; shared projects always use project-only memory | Each project has its own memory; “Use account memory” can be turned off |
| Coming change | None announced | A beta version where a project is one conversation, starting in Claude Code |
Two details catch people out. In Claude, what you say in one chat of a project does not reach the others unless you add it to the project’s knowledge. In ChatGPT, outside Enterprise and Edu, chats in a project can still draw on your conversations outside it, unless the project uses project-only memory.
Perplexity also has Projects, private by default, with up to 10,000 files, 5 GB in total, and five contributors on a personal account; we found no page saying which plans include them.
Custom GPTs: the retirement timeline
OpenAI’s FAQ, updated on November 10, 2026, gives these dates and rules:
- December 11, 2026: standard retirement date on every plan; February 11, 2027 for FedRAMP workspaces and approved exceptions.
- Personal accounts (Free, Go, Plus, and Pro) can no longer create or publish GPTs; existing ones can still be used and edited until retirement.
- Enterprise workspaces stopped creating GPTs on October 26, 2026.
- Migration: “Migrate to plugin” in My GPTs turns the instructions into a skill and the knowledge files into reference files, and carries over connected apps. It takes only the last published version, drops the chosen model and any custom actions, and makes the plugin private at first; the original GPT becomes read-only.
- After retirement, GPTs and their pages can no longer be opened, but your past conversations with them remain.
OpenAI’s pricing page still listed custom GPTs for Plus and Pro on November 10, 2026. The help center is more recent and is the reference here.
Gems become skills
Google’s Gems transition page sets two dates for personal accounts of people aged 18 and over. On November 17, 2026, Gems become read-only: you can see them but no longer use, edit, or create them. On December 17, 2026, they are removed. Google recreates each Gem as a skill automatically, with up to 100 MB of files, removing the largest first, and leaves out audio, video, archives, and older .doc, .xls, and .ppt files. Download any file you need before December 17. Workspace business, enterprise, and nonprofit accounts follow in March 2027, education accounts in June 2027.
A shared format for reusable instructions
Claude’s skills are folders built around a file named SKILL.md, and Anthropic has published the format as an open standard. Microsoft’s skills in Excel and Gemini’s skills accept SKILL.md files too, and ChatGPT plugins now carry skills of their own. The practical consequence: write your instructions in a plain text file that you keep yourself, and you can move them from one assistant to another.
Before December: a checklist
Our recommendation for a small team:
- List your GPTs and Gems, with who uses each one and for what.
- Copy each one’s instructions and files into a folder your business controls.
- Migrate or rebuild: a plugin or skill for a repeated method, a project for ongoing work with documents.
- Recreate custom actions separately, since the migration drops them.
- Review who can open each shared project, and remove files that should not be there.
Writing the instructions once
Project instructions and skills are prompts you reuse. See how to write a prompt that gets results, with a structure that works for both.
Asking questions about the project’s files
A project is often a pile of contracts, notes, and reports. Our page on summarizing long documents covers the file limits and how to check a summary.