AI System Prompt Builder

Build effective system prompts step by step. Choose a persona, tone, output format, and constraints to generate optimized prompts for GPT, Claude, Gemini, or any AI model.

Quick-Start Presets
1. Role & Persona
Preset Roles
Custom Role
Years of Experience
2. Tone & Style
Tone
Communication Style
3. Output Format
Format
Language
4. Constraints & Rules
Quick-Add Constraints
Custom Rules (one per line)
5. Context & Domain
Domain / Industry
Target Audience
Tools / Tech Stack
Generated System Prompt
Start filling in the form on the left to generate your system prompt. Pick a quick-start preset above to get started quickly.

This tool runs entirely in your browser. No data is sent to any server. The generated prompt is a starting point -- customize it further for your specific use case.