Claude Skills vs ChatGPT GPTs: what is the difference?
Claude Skills are instruction folders Claude loads when needed. GPTs are custom ChatGPT versions. How they differ, who can make each, and which to use.
Short answer
A Claude Skill is a folder with a SKILL.md file of instructions, plus optional scripts and reference files, that Claude loads only when a task needs it. A GPT is a custom version of ChatGPT that you set up with instructions, up to 20 knowledge files and optional actions, then share as its own chat. Use a skill when you want Claude to do a repeatable job inside your normal work, especially in Claude Code. Use a GPT when you want a separate assistant others open in ChatGPT, and note that OpenAI now limits creating GPTs to Business, Enterprise and Edu workspaces.
Side by side
| Claude Skill | ChatGPT GPT | |
|---|---|---|
| What it is | A folder with SKILL.md plus optional scripts and files | A custom ChatGPT with instructions, knowledge files and capabilities |
| How it starts | Claude loads it when relevant, or you type /skill-name | The user opens that GPT as its own chat |
| Context cost | Only the description stays loaded; the body loads when used | Instructions apply to every chat with that GPT |
| Can run code | Yes, bundled scripts run in Claude Code | Through Code Interpreter and actions to external APIs |
| Files | Any reference files in the folder, read when needed | Up to 20 knowledge files, each up to 512 MB |
| Where it works | Claude Code, claude.ai uploads and the API; follows the open Agent Skills standard | ChatGPT; mobile apps can use GPTs but not create them |
| Who can make one | Anyone can write the folder; sharing works through projects and plugins | Business, Enterprise and Edu workspaces; not personal Free, Go, Plus or Pro accounts |
| Sharing | Commit it to a repo, a plugin, or your claude.ai account | Share link or the GPT Store |
When to use which
- A repeatable job you do inside a project, like writing captions in your voice or reviewing code: a Claude Skill.
- A job that needs to run real scripts or read files in your folder: a Claude Skill in Claude Code.
- A ready assistant you hand to a team or clients inside ChatGPT: a GPT, if your workspace allows creating one.
- You want the same instructions to work across tools: skills follow an open standard used by more than one AI tool.
Free skills you can install today
I write install guides for open source skills I test on camera: Instagram Agent Skill, YouTube Agent, LinkedIn skills and Replica Skill. Each guide credits the original author and links to the repository.
Questions
Are Claude Skills the same as GPTs?
No. A GPT is a separate custom chat in ChatGPT. A Claude Skill is a folder of instructions and optional scripts that Claude pulls into your existing work only when it is relevant.
Can I still create a GPT on ChatGPT Plus?
According to OpenAI's help article on creating GPTs, new GPT creation and publishing are not available on personal accounts, including Free, Go, Plus and Pro. They are limited to Business, Enterprise and Edu workspaces.
Do Claude Skills work outside Claude Code?
Yes. Skills can be uploaded to claude.ai and used through the API, with a limited set of fields. Claude Code supports the most features, such as running bundled scripts.
Do I need to code to make a Claude Skill?
No. A skill can be only a SKILL.md file with a name, a description and plain instructions. Scripts are optional.