AI prompt optimizer
Turn a rough prompt into a structured one for a chat, reasoning or image model, with a list of what changed.
Your key stays in your browser.It goes straight to the provider, never to our servers, and we neither log nor keep it. Use a dedicated key with a spending cap, and delete it in the provider's dashboard when you are done.
Input
Result
The result will appear here.A one-line prompt leaves the model to guess the audience, the length, the format and what to do about missing facts, and it usually guesses blandly. Paste the prompt you were about to send and this rewrites it into labelled parts — role, context, task, constraints, output format — keeping every requirement you gave and marking the gaps with placeholders such as [target audience] instead of filling them with inventions. Under the rewrite come three to six bullets saying what changed and why, so you pick up the pattern rather than just copying the result. Choose the target first: a reasoning model wants a short statement of goal and constraints rather than step-by-step scaffolding, and an image model wants subject, style, lighting and composition rather than a role.
How it works
- Three targets, three rule sets: chat models get Role / Context / Task / Constraints / Output format; reasoning models (the o-series, DeepSeek-R1, anything with extended thinking) get a lean prompt with no chain-of-thought instructions; image models get one descriptive prompt plus aspect-ratio and negative-prompt lines.
- The rewriting rules condense the six prompt-engineering strategies quoted in Fabric's improve_prompt pattern, and the model is told that your text is something to rewrite, never something to answer.
- linshenkx/prompt-optimizer (30k+ stars, AGPL-3.0) is the open-source app built for this job, with side-by-side testing and history; this page is a lighter, no-install take on the same idea, with a prompt of its own.
- The rough prompt and your key travel from this tab straight to the provider you pick; a key made just for this, with a spending cap, is the one to use, and it is worth revoking once you are done.
Where your data goes
With your own key, what you type and the key go from your browser straight to the provider you choose; neither passes through Hysen Labs. In hosted mode, your text goes through our server to our provider (DeepSeek) and is billed in credits; we keep the token counts and cost of each run for billing, never the text itself or the answer. How the provider handles the text is governed by its own privacy policy.
This tool handles keys and credentials, so nothing about a run is saved, not even to your own history.
About your API key
We do not collect, store or leak your key: it lives only in this page's memory (unless you tick “remember in this tab”) and is gone when you close it. Still, treat any key you have pasted into a web page with care — create a dedicated key with a spending cap for use here, and delete or rotate it in your provider's dashboard when you are done.
What it costs
This tool is free, with no sign-in and no points.
Common questions
- Why does the optimized prompt contain things like [target audience]?
- Because your original did not say, and the alternative is the model making something up. Replace each bracketed placeholder with the real value before you send the prompt. A prompt whose gaps you filled beats one whose gaps were filled by a guess.
- Should I use the reasoning-model target for o-series models or DeepSeek-R1?
- Yes. Reasoning models plan their own approach, and OpenAI's guidance for its reasoning models is to keep prompts simple and direct and not to script the chain of thought. The reasoning target drops 'think step by step' instructions and elaborate personas and keeps the goal, the constraints and the expected output.
- Why is the image prompt in English when I wrote in Chinese?
- Most image models, Stable Diffusion and FLUX among them, follow English prompts more reliably, so that is the default. If your model handles Chinese well, say so in the rough prompt and the rewrite stays in Chinese. The notes on what changed are in your language either way.
- Is the prompt I paste kept anywhere?
- Not by this site. The request goes from your browser to the provider under your own account, so the provider's data policy is the one that applies — check it before pasting anything confidential, since some providers retain API inputs for a period to monitor abuse.
The open-source behind it
This tool is a self-contained implementation. linshenkx/prompt-optimizer (AGPL-3.0-only) does the same job as a library — if you need this behaviour inside your own program, start there rather than calling a web page.
linshenkx/prompt-optimizerAlso known as
- prompt optimizer
- prompt generator
- improve chatgpt prompt
- prompt engineering tool
- ai prompt rewriter
- midjourney prompt generator