A ChatGPT prompt generator that follows OpenAI’s own advice
This ChatGPT prompt generator lays out your prompt the way OpenAI’s documentation recommends: instructions first, pasted text fenced off with triple quotes, examples that show the exact format and, for developers, rules in a developer message kept apart from the user’s request. Fill in the form or start from one of 19 templates.
You get four versions of the same prompt — plain text to paste into a ChatGPT chat, Markdown, a JSON array of developer and user messages for the OpenAI API, and a short block for ChatGPT’s custom instructions, measured against each plan’s character limit. A rule-based checklist catches vague and contradictory wording before you send it.
How to write a ChatGPT prompt here
- Choose a template or start blank, and fill in any variables.
- Describe the Identity and Your request; add context, audience, steps, rules and examples if they help.
- Set the output format, tone, length and language.
- Read the Prompt checklist, then pick a view: Plain text for a chat, JSON for the API, Custom instructions for settings.
- Copy or download it, or keep it with Copy share link and Save to favourites.
ChatGPT Prompt Generator features
Chat, API and settings from one form
A chat prompt, a developer + user message array and a custom-instructions block, always in sync.
OpenAI’s developer-message order
Identity, then Instructions, Examples and Context, as in OpenAI’s prompt-engineering guide.
Examples in two styles
<user_query> / <assistant_response> pairs for the API; Input/Output pairs separated by ## for the chat.
Custom-instructions length check
Counted against 1,500 characters (Free, Go) and 5,000 (paid plans).
Contradiction checks
Short versus detailed, formal versus casual, clashing formats and impossible word limits are flagged.
What OpenAI recommends, and how this page applies it
- Instructions first, context fenced off. OpenAI’s Help Center suggests starting with the instruction and separating context with ### or """. The chat version ends with
Context: """ … """. - Be specific about outcome, length, format and style. Its own example swaps “fairly short” for “a 3 to 5 sentence paragraph” — fill the Length box the same way.
- Show the format. Start without examples and add a few when the shape of the answer matters.
- Say what to do, not only what not to do. The checklist warns when most rules start with “don’t”.
- Developer messages outrank user messages. OpenAI compares them to a function and its arguments.
- Avoid contradictions. OpenAI’s GPT-5 prompting guide (2025) says contradictory or vague instructions cost reasoning models extra effort.
Sources, checked 14 October 2026: OpenAI’s API guide “Prompt engineering” (developers.openai.com), the Help Center articles “Best practices for prompt engineering with the OpenAI API” and “ChatGPT Custom Instructions”, and the GPT-5 prompting guide in the OpenAI Cookbook.
Developer message, user message or custom instructions?
The JSON view is the input array for OpenAI’s Responses API, which takes the developer role; add your model name and settings. Some older code expects a "system" role instead — rename it if yours does.
Custom instructions sit under Settings → Personalization in ChatGPT on the web and desktop (Customize ChatGPT on iOS and Android) and apply across your chats. OpenAI lists 1,500 characters for Free and Go and 5,000 for Plus, Pro, Business, Enterprise and Education, and offers no API for them — developers use system or developer messages instead.
| Where | What belongs there | View to copy |
|---|---|---|
| Developer message (API) | Identity, rules, format, examples, reference text | JSON, first message |
| User message (API) | The request and its audience | JSON, second message |
| A ChatGPT chat | Everything in one message, instructions first | Plain text |
| Custom instructions | Standing preferences: role, tone, length, language, rules | Custom instructions |
Worked example
The “Ad headline ideas” template, with the offer “a free 14-day trial of a budgeting app” and the audience “university students in the UK”, gives this chat prompt:
You are a performance marketer.
Write 10 headline options for an online ad promoting a free 14-day trial of a budgeting app.
Audience: university students in the UK
Instructions:
- Keep each headline under 30 characters
- Vary the angle: price, speed, quality, social proof and curiosity
- Respond with a numbered list.
- Tone: confident.In the JSON view, the Identity and Instructions become the developer message and the request becomes the user message. To rework existing text in another voice, the tone changer may be quicker than a prompt.
ChatGPT Prompt Generator FAQ
How do I write a good ChatGPT prompt?
Give it a role, one clear request, the context it cannot know, the format and length you want and, when the format matters, an example. Put instructions before long pasted text and fence that text with triple quotes. This ChatGPT prompt generator does that layout for you.
What is the difference between a developer and a system message?
They do the same job: instructions from the app’s developer that outrank the user’s messages. OpenAI’s current documentation says “developer”; many older examples and libraries say “system”.
Where do custom instructions go, and how long can they be?
Settings → Personalization → Custom instructions on the web and desktop, or Customize ChatGPT in the mobile apps. Free and Go save up to 1,500 characters; paid plans up to 5,000.
Does ChatGPT understand Markdown and XML tags in a prompt?
Yes. OpenAI’s guide recommends Markdown headings and lists to mark sections and XML tags to show where a document or example starts and ends.
Is this tool made by OpenAI?
No. It is an independent page that follows OpenAI’s published guidance. It does not connect to ChatGPT; you copy the prompt yourself.