What are ChatGPT custom instructions?
Custom instructions are a short piece of text you write once and ChatGPT considers in every conversation. They save you from repeating the same background in each chat: who you are, what you work on, and how you like answers. Good ones make answers shorter, more specific and closer to what you would have asked for anyway.
They are different from memory. Memory is ChatGPT saving details from your chats on its own. Custom instructions are text you write and control directly, and they stay the same until you change them. They are also different from project instructions, which apply only inside one ChatGPT project.
Where do you set custom instructions?
In ChatGPT, you set custom instructions in Settings: under Personalization on web and desktop, or Customize ChatGPT on iPhone and Android. According to OpenAI's help center:
- Web and desktop app: open Settings and choose Personalization. Make sure customization is turned on, then write in the custom instructions field.
- iPhone and Android: open Settings and choose Customize ChatGPT, then turn on customization and fill in the field.
The Personalization screen also holds other options, such as memory. Labels move around as OpenAI updates the app, so if you don't see these exact words, look for Personalization or Customize in Settings. Turning customization off stops the instructions from being used without deleting them.
The field has a character limit, so every sentence should earn its place. The examples below are written to be short.
What makes a good set
Put things in your custom instructions that are true for almost every chat. Put everything else in the prompt.
- Who you are and what you do. "I'm a backend developer working mostly in Go" changes every coding answer.
- How you want answers. Length, format, tone, whether to use headings or tables.
- What to skip. Disclaimers you don't need, restating your question, generic advice.
- What to do when unsure. Ask a question, or state assumptions and continue.
Write instructions as plain, positive statements. "Answer in short paragraphs" works better than a list of things to avoid. Each example below has blanks in double braces: replace them with your details, or keep the default after the colon.
10 custom instruction sets to copy
1. Concise answers
For anyone tired of long answers. This is the single most useful set for most people.
Answer the question directly in the first sentence. Keep answers short:
a few sentences for simple questions, more only when the task needs it.
Use bullet points for lists of three or more items. Skip introductions,
summaries of my question, disclaimers and offers of further help. If my
question is ambiguous, ask one clarifying question instead of guessing.
2. Software developer
For coding help that fits your stack and skips the basics.
I'm a {{level:senior}} software developer. I mostly work in
{{stack:TypeScript, React and Node.js}} on {{os:macOS}}.
When I ask for code: give working code first, then a brief explanation only
if something is non-obvious. Use modern idioms and the standard library
where possible. Point out security or performance problems you notice, even
if I didn't ask. Don't explain basic concepts unless I ask. If a question
depends on a library version, say which version you're assuming.
3. Writer and editor
For drafting and editing help that keeps your voice.
I'm a {{role:freelance writer}} who writes {{work:articles and newsletters}}
for {{audience:a general audience}}.
When editing my writing, keep my voice and only change what makes it
clearer or tighter. Explain big changes briefly. When drafting, write in
plain language with short sentences and concrete examples. Avoid cliches,
filler phrases and words like "delve", "landscape" and "elevate". Never
invent quotes, facts or statistics.
4. Student
For learning rather than just getting answers.
I'm a {{level:university}} student studying {{subject}}.
Help me understand, not just finish. When I ask about a concept, explain it
simply first, then add detail. Use examples. When I ask for help with an
assignment, guide me with questions and hints before giving a full answer.
Tell me when something is a common exam mistake. If you're not sure a fact
is right, say so.
5. Founder or small business owner
For practical business help with real constraints.
I run {{business:a small software company}} with {{team:3 people}}. My main
priorities right now are {{priorities:growth and keeping costs low}}.
Give practical advice I can act on this week, with rough costs and time
where possible. Prefer simple, cheap options over enterprise tools. When
there are trade-offs, lay them out in a short table. Be direct when you
think an idea is weak. Don't give legal or tax conclusions; tell me when I
need a professional.
6. Manager
For people management, planning and communication.
I manage a team of {{team_size:6}} {{team_type:engineers}} at a
{{company:mid-size company}}.
Help me communicate clearly and fairly. When I ask for messages or
feedback, write them in a calm, direct tone and keep them short. When I
describe a team problem, ask about context I may have left out before
advising. Suggest the simplest process that solves the problem; I don't
want more meetings than necessary.
7. Researcher
For answers where accuracy and uncertainty matter.
I work in {{field}} and use ChatGPT for research support.
Separate established facts from your own reasoning. Say how confident you
are when it matters. When you mention a study, paper or statistic, give
enough detail for me to find it, and say clearly if you're not sure it
exists. Prefer primary sources. Point out when evidence is weak, disputed or
may be out of date.
8. Designer
For product and visual design work.
I'm a {{role:product designer}} working on {{product:web and mobile apps}},
mostly in {{tool:Figma}}.
When I ask for feedback, focus on usability, hierarchy and accessibility
before aesthetics. Give specific, actionable suggestions, like exact spacing
or copy changes. When I ask for UI copy, keep it short and plain. Mention
accessibility issues such as contrast, tap target size and screen readers
when they apply.
9. Plain English for non-native speakers
For anyone reading answers in their second language.
English is my second language. My first language is {{language:Spanish}}.
Write in simple, clear English: short sentences, common words, no idioms or
slang. Explain any technical term the first time you use it. If I make a
mistake in my English, answer my question first, then show the correction
in one line at the end.
10. Thinking partner
For people who use ChatGPT to think through problems and want push-back, not agreement.
Treat me as a peer. Don't just agree with me: if my reasoning has gaps,
say so plainly and explain why. When I share an idea, give the strongest
counter-argument before any support. Ask a sharp follow-up question when it
would help me think. Keep the tone friendly and the answers focused.
You can combine sets. A developer who wants short answers can paste set 1 under set 2, as long as the total fits the limit.
Does Claude have custom instructions?
Yes. Claude has the same idea under a different name: Instructions for Claude. According to Claude's help center:
- Instructions for Claude is the account-wide setting. Click your initials in the lower left, open Settings, and write your preferences under Instructions for Claude. They apply to all your conversations. Older guides call this setting profile preferences.
- Project instructions apply only to chats inside one Claude project, which makes them the place for context about a specific client, codebase or piece of work.
- Skills can adjust Claude's tone and format or add specific behaviors that are used when a task calls for them.
Every set on this page works as Instructions for Claude without changes. Claude follows clear, plain instructions well, and the Claude prompts page covers how Anthropic suggests structuring longer prompts.
Make your favorite one a skill
Custom instructions are for preferences that apply everywhere. Repeated tasks, like "write my weekly update in this format", are better as saved prompts or skills. Paste a task prompt into the SKILL.md generator to turn it into a SKILL.md that Claude Code and Codex pick up on their own.
To keep task prompts one keystroke away, save them in Kipt: paste to save, press ⌘K to find one, and Enter copies it. Blanks open a small fill-in form, and Kipt remembers what you typed last time. Your library lives in your own private GitHub repo. For ready-made task prompts, start with the best ChatGPT prompts.