Prompt Optimizer takes your rough AI prompts and rewrites them to get better results from any AI model. Run it free in your browser or deploy your own private copy on Vercel in minutes.
The fastest way to start is the hosted version at prompt.always200.com. Everything runs inside your browser — no data is sent to any server other than the AI provider you choose. This is the recommended starting point for most people.
The tool needs an API key to talk to an AI model on your behalf. It never stores your key on any server — it lives only in your browser's local storage. Click the settings or model configuration area, pick your provider (OpenAI, Gemini, DeepSeek, etc.), and paste your key. You also choose which model to use for optimization and which to use for testing.
The app shows an authentication error when you try to optimize.
Double-check that you copied the full API key with no extra spaces. Make sure the key has billing enabled on your provider's dashboard.
Type or paste the prompt you want to improve into the main input box. Hit the Optimize button. The tool sends your prompt to the AI model, which rewrites it to be clearer and more effective. You can run multiple rounds of optimization to keep improving it.
Optimization takes very long or times out.
Try a faster or cheaper model like DeepSeek or Gemini Flash in settings. Long prompts take more time.
Before you use the new prompt, test it. The app has a built-in testing panel where you can run both the original and optimized prompts side by side and compare the AI outputs. This tells you whether the optimization actually helped. You can also run an automated evaluation to score the results.
Both responses look identical or the optimized one seems worse.
Try another round of optimization, or switch to a more capable model (e.g. GPT-4o or Gemini 1.5 Pro) for the optimization step.
Once you are happy with a prompt, save it. The favorites system keeps version history so you can always go back to an earlier version. Everything is stored locally in your browser — nothing leaves your machine.
If you want a permanent private URL — for example to share with a team — deploy your own copy. Fork the GitHub repo to your account, then import it into Vercel. You can set an ACCESS_PASSWORD environment variable so only people you share the password with can use it. You can also pre-fill API keys as environment variables so users do not need to enter them.
The Vercel build fails with a TypeScript or dependency error.
Make sure you forked the repo rather than just linking the original. In Vercel's project settings set the Framework Preset to Vite if it was not detected automatically.
You end up with a polished, tested prompt saved in your favorites, plus an optional private web app your team can use without any coding.
This tool improves prompts — it does not guarantee better AI outputs every time. Results depend heavily on which AI model you use and how clear your original intent is. The online version stores everything in your browser; clearing browser data will erase your saved prompts, so export your favorites regularly. The image generation features require API keys from providers that support image models (Gemini, Grok, etc.) and those calls cost money per image.