Free · No sign-up
Free AI Prompt Optimizer
Enter any prompt and instantly get an optimized version, a quality score, and exactly what improved — and why.
Free · no sign-up · ⌘/Ctrl + Enter to run
How it works
Enter your prompt
Type or paste any prompt — a question, a task, a rough idea. No account, no setup.
Get the optimized version
We rewrite it with clear context, a format, and an expert persona — and score the before vs after.
See the real answer
Run the optimized prompt on the best model — or several at once — free at Mycelio.
Better prompts, better answers
Most AI answers fall short because the prompt was vague — missing context, format, or focus. A well-engineered prompt does the heavy lifting: it tells the model who to be, what you need, and how to deliver it. This tool handles that for you in one click, then shows the difference so you learn what makes a prompt strong.
Frequently asked questions
What does the prompt optimizer do?
It rewrites your prompt to be clearer and more effective. Adding context, a desired output format, and an expert persona, then scores the before and after across clarity, specificity, context, and structure so you can see exactly what improved.
Free, with no sign-up?
Yes. Optimizing a prompt here is completely free and requires no account. If you want the actual answer, generated by the best model for your prompt, you can create a free Mycelio account to view your answer.
How is the prompt score calculated?
An AI prompt-engineering model rates your prompt on four axes — clarity, specificity, context, and structure, from 0 to 10, before and after the rewrite. The 0–100 headline score is the average of those axes, so the number always matches the breakdown.
What is the best model for my prompt?
The optimizer also tells you which model Mycelio would route your prompt to. For example a strong reasoning model for analysis, or a fast model for quick tasks. At Mycelio, that routing happens automatically through auto or refine mode.
How is this different from just using ChatGPT?
This tool focuses purely on the prompt: it engineers a better version and shows you why. Mycelio goes further, it optimizes your prompt and automatically routes it to the best model across Claude, GPT, Gemini, and more, so you get better answers automatically.
How do I compare my answer to different models?
Open your chat at Mycelio, then under any AI answer tap the branch iconlabeled “Ask another model.” Pick a different model and Mycelio generates its take, so you can compare answers across Claude, GPT, Gemini, and more on the same prompt.
Get the answer, not just the prompt
Mycelio optimizes your prompt and routes it to the best AI model automatically — Claude, GPT, Gemini, and more. Start free with 200 credits, no card needed.
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