Free AI & Prompt Tools
AI and prompt tools help you build structured prompts for ChatGPT, Claude, Gemini, and Midjourney. Count tokens against model context windows, write system prompts visually, and generate image prompts with style, lighting, and aspect ratio controls — all without needing an API key. Your prompts never leave your browser.
4 tools available
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Build structured AI prompts with role, context, task, tone, format, and constraints. Works with ChatGPT, Claude, Gemini, and any LLM.
Try it free →Token CounterCount approximate tokens in your text for GPT-4, Claude, Gemini, and Llama. See context window usage and estimated API cost per model.
Try it free →System Prompt BuilderBuild structured system prompts for ChatGPT, Claude, and Gemini visually. Toggle sections, load templates, and copy the final prompt.
Try it free →All AI & Prompt Tools (4)
Build structured AI prompts with role, context, task, tone, format, and constraints. Works with ChatGPT, Claude, Gemini, and any LLM.
Open tool →Token CounterCount approximate tokens in your text for GPT-4, Claude, Gemini, and Llama. See context window usage and estimated API cost per model.
Open tool →System Prompt BuilderBuild structured system prompts for ChatGPT, Claude, and Gemini visually. Toggle sections, load templates, and copy the final prompt.
Open tool →AI Image Prompt BuilderGenerate AI image prompts for Midjourney, DALL·E 3, Stable Diffusion, and Firefly. Choose style, lighting, camera, mood, and aspect ratio.
Open tool →Frequently Asked Questions
- Do I need an API key to use these tools?
- No. All AI prompt tools on Stax work without any API key. They help you build, structure, and count tokens in prompts — you then copy and use them in any AI interface like ChatGPT, Claude, or Gemini.
- Are AI prompt tools free?
- Yes. All tools are completely free with no sign-up, no usage limits, and no subscription required.
- Which AI models do the prompts work with?
- Prompts built with Stax tools work with any text-based LLM — ChatGPT (GPT-4o), Claude, Gemini, Llama, Mistral, and others. The image prompt builder specifically targets Midjourney, DALL·E 3, Stable Diffusion, and Firefly.
- Is my prompt data stored?
- No. All prompt building and token counting runs in your browser. No prompt text is sent to any Stax server.
- How accurate is the token counter?
- The token counter uses the cl100k_base tokenizer (used by GPT-4 and Claude) for estimates. Exact token counts may vary slightly by model version — use this as a close approximation when planning context window usage.