Free AI Prompt Generator
Turn a rough idea, or a weak prompt, into a clean, structured system prompt for ChatGPT, Claude, and Gemini. No login. It builds the prompt right in your browser, so you get a real result the moment you start typing.
Your structured prompt
You are a knowledgeable expert assistant focused on the task below.
Type your idea on the left and this fills in with real, tailored context.
Your goal, rewritten as a clear instruction, appears here.
- Stay on task - Ask one clarifying question if a detail is missing - Never fabricate facts
Respond in clear prose. Do not use em dashes.
None yet. Turn on the Add examples chip to include a worked example.
Built in your browser. Nothing you type is stored or sent anywhere unless you tap Sharpen with AI.
A good prompt in three steps
No prompt engineering knowledge required. The framework does the work.
Describe the goal
Type a rough idea, or paste a weak prompt you want to fix. One sentence is enough to start.
Set the shape
Pick the target model, tone, output format, and audience. Add refine chips like More concise or Add constraints.
Copy the structured prompt
Get a clean prompt split into Role, Context, Task, Constraints, Output format, and Examples. Copy it as text or Markdown.
Role, Context, Task, Constraints, Format, Examples
The six-part structure behind every strong prompt. Learn it once and your prompts get dramatically better.
Who the AI should be. A clear role sets expertise, voice, and point of view before the task even starts.
What the AI needs to know. The audience, the target model, background facts, and anything that shapes a good answer.
The one thing to do, written as a direct instruction. Not a vague wish, an actual command.
The rules and limits. Length, tone, what to avoid, when to ask a clarifying question, and never to fabricate facts.
Exactly how the answer should look. Prose, bullets, a table, JSON, or Markdown. Ambiguity here is where most prompts fail.
One or two worked examples when the format is unusual. Examples teach faster than description.
write me a marketing email for my product
No role, no audience, no format, no constraints. The model has to guess, so you get a generic draft you have to rewrite anyway.
Role: a senior B2B copywriter. Context: audience is busy CTOs. Task: write a cold email that books a demo. Constraints: under 120 words, one clear ask, no hype. Output format: subject line plus body.
Same idea, structured. The model knows exactly what to produce, so the first draft is usable.
The same prompt, tuned for each model
A strong prompt is portable, but each assistant has a personality. The generator adds a short model note to the Context so your prompt fits how each one behaves. Here is what changes.
| Model | Where it shines | How to prompt it |
|---|---|---|
| ChatGPT | Follows an explicit system role tightly and is strong at structured output like JSON and tables. | Put your rules in a clear Role and Constraints block, and name the exact output format. GPT rewards specificity and will hold a persona across a long chat. |
| Claude | Excels at long context, careful reasoning, and following nuanced instructions without over-explaining. | Ask it to think step by step, and use clear section labels or XML-style tags so it can separate context from the task. Claude prefers structure over stern commands. |
| Gemini | Fast, direct, and good at grounded, factual answers when the task is unambiguous. | Be concrete and remove hedging language. Spell out the format and the constraints up front, because Gemini does best when there is nothing left to guess. |
Not sure which to target? Pick Any and the prompt stays portable across all three. The Role, Context, Task, Constraints, Output format, and Examples structure is what does the heavy lifting on every model, so a well-built prompt travels well.
Better prompts for every kind of work
Marketers and writers
Spin up reliable prompts for cold emails, blog outlines, ad copy, and social posts that keep your voice and brief.
Developers
Build a repeatable coding assistant prompt that reviews code, explains errors, and returns clean diffs.
Operators and PMs
Turn meeting transcripts into decisions and action items, or draft crisp specs, with a prompt you can reuse every week.
Anyone new to AI
Stop guessing. The framework does the heavy lifting so you get good results without learning prompt engineering first.
Save these as reusable Contexts in Contextli
A great prompt is only useful if you can reach for it again. Contextli lets you save your writing modes as Contexts and trigger them by voice, everywhere you type. Do this by voice, everywhere. Download Contextli free.