Prompt Optimizer
An AI prompt optimizer for writing better prompts and getting better AI results.
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What is Prompt Optimizer?
Prompt Optimizer is an open-source AI prompt optimization tool with 23k+ GitHub stars that helps users transform vague or unclear prompts into precise, high-quality instructions for AI models. The tool uses intelligent algorithms to deeply analyze original prompts and perform multi-round iterative optimization, ensuring AI models like GPT-4, Claude, Gemini, and even smaller 7B models produce stable, high-quality outputs.
Key features include one-click smart optimization that automatically fills in missing details and corrects semantic gaps, real-time dual-screen comparison showing original vs. optimized prompt results side-by-side, pure client-side architecture ensuring data privacy (all data stays in browser, no intermediate servers), support for both system prompts and user prompts, built-in text-to-image and image-to-image generation capabilities, Chrome browser plugin for on-the-fly optimization, Docker/Vercel private deployment options, MCP protocol support for Claude Desktop integration, multiple workspaces for different use cases (system prompts, user prompts, variables, multi-message context, image generation), prompt garden library for discovering ready-to-use prompts, and local encryption for API keys and history.
This tool is ideal for workplace professionals who need consistent AI output for business tasks, content creators and writers seeking better creative results, students learning to use AI effectively, developers working with local Ollama deployments, teams requiring private/self-hosted solutions, and anyone frustrated with AI providing irrelevant or low-quality responses to their prompts.
Prompt Optimizer pricing
Pricing model: Freemium
Completely free and open-source under AGPL-3.0 license. No paid tiers or subscription plans. All core features are available for free including online version, Chrome plugin, desktop app, and Docker deployment. Users only pay for their own AI API usage (OpenAI, Claude, Gemini, etc.). Commercial use is allowed but derivative works must also be open-sourced.
Prompt Optimizer pros
- Completely free and open-source with AGPL-3.0 license
- 23k+ GitHub stars with active community (23 contributors)
- Pure client-side architecture - data never leaves browser
- One-click optimization transforms vague prompts to precise instructions
- Real-time side-by-side comparison of original vs. optimized results
- Supports GPT-4, Claude, Gemini, DeepSeek, Ollama, and more
- Chrome plugin available for optimization while writing prompts
- Built-in text-to-image and image-to-image generation
- Docker and Vercel one-click private deployment supported
- MCP protocol support for Claude Desktop integration
- No registration required for online version
- Chinese-friendly interface with comprehensive documentation
- Multiple workspaces for different prompt types and contexts
- Local encryption for API keys and conversation history
- Reduces prompt debugging time by 60%
- Improves AI output quality by 70-300%
- Responsive design works on mobile devices
- Prompt Garden library for discovering ready-to-use prompts
Prompt Optimizer cons
- Requires manual API key configuration for first use
- Must configure at least one text model before starting
- Online version stores data only in browser (no cloud backup)
- No native mobile app (browser-only on mobile)
- Advanced features require understanding of prompt engineering
- Self-hosted deployment needs technical knowledge
- Limited to models with API access (no built-in model hosting)
- Derivative works must remain open-source under AGPL-3.0
Frequently asked questions about Prompt Optimizer
What is Prompt Optimizer and what does it do?
Prompt Optimizer is an open-source AI prompt optimization tool that transforms vague or unclear prompts into precise, high-quality instructions. It uses intelligent algorithms to analyze your original prompt, identify semantic gaps, automatically补充 missing details, and perform multi-round iterative optimization. The tool supports GPT-4, Claude, Gemini, DeepSeek, Ollama, and other models, letting them produce stable, high-quality outputs consistently.
Is Prompt Optimizer free to use?
Yes, Prompt Optimizer is completely free and open-source under the AGPL-3.0 license. There are no paid plans, subscriptions, or premium tiers. All features including optimization, comparison, text-to-image, Chrome plugin, and Docker deployment are available for free. You only pay for your own AI API usage when connecting to services like OpenAI, Claude, or Gemini.
How do I start using Prompt Optimizer for the first time?
First, visit https://prompt.always200.com in your browser (no registration required). Click the gear icon in the top-right to configure your API key for OpenAI, Gemini, DeepSeek, or other models. Then enter your original prompt in the left panel (like 'write a poem about spring'), click 'Optimize Prompt', view the side-by-side comparison of original vs. optimized results, and copy the optimized version with one click.
Is my data and API key secure with Prompt Optimizer?
Yes, Prompt Optimizer uses a pure client-side architecture. All data communicates directly with AI service providers without passing through any intermediate servers. Your API keys and conversation history are encrypted and stored locally in your browser. Even the developers cannot access your data. This makes it one of the most privacy-focused prompt optimization tools available.
What models does Prompt Optimizer support?
Prompt Optimizer supports OpenAI (GPT-4, GPT-3.5), Claude, Gemini, DeepSeek, Zhipu, SiliconFlow, and Ollama (compatible with OpenAI interface). You can configure multiple models and switch between them. The tool also supports both system prompts and user prompts, and even works with local Ollama deployments for 7B and other small models.
What workspaces are available in Prompt Optimizer?
There are multiple workspaces: System Prompt workspace for optimizing role, rules, boundaries and output specifications; User Prompt workspace for optimizing direct task prompts sent to models; Variables workspace for creating reusable templates; Multi-message workspace for optimizing within full conversation context; Text-to-Image workspace for comparing image generation prompts; Image-to-Image workspace for optimizing with reference images; and Multi-image workspace for using multiple input images to constrain generation.
Can I use Prompt Optimizer on mobile devices?
Yes, you can access the online version at https://prompt.always200.com through any mobile browser. The interface has responsive design that automatically adapts to mobile screen sizes. However, there is no dedicated native mobile app - mobile users access it through their browser like desktop users.
How do I deploy Prompt Optimizer privately using Docker?
Use this command: docker run -d -p 8081:80 -e VITE_OPENAI_API_KEY=your_key -e ACCESS_PASSWORD=your_password --name prompt-optimizer linshen/prompt-optimizer. This supports password protection for access. For Chinese users, you can use the domestic mirror: registry.cn-guangzhou.aliyuncs.com/prompt-optimizer/prompt-optimizer for faster download speeds.
What is the difference between optimization, testing, and evaluation modes?
Optimization transforms your original prompt into a better version through intelligent analysis. Testing lets you run the optimized prompt and see actual AI output. Evaluation includes three types: Analysis (understanding prompt structure), Evaluation (assessing quality), and Comparative Evaluation (directly comparing original vs. optimized results side-by-side to witness quality improvements).
Can I use Prompt Optimizer commercially in my business?
Yes, commercial use is allowed under the AGPL-3.0 license. However, the copyleft clause means that if you modify the code and distribute it, your derivative works must also remain open-source under the same AGPL-3.0 license. Using it internally within your company without distribution is fully permitted.