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AI Prompt Builder

100% Client-Side Private — Zero Server Uploads

Build and customize AI prompts from 10 hand-written templates for coding, writing, marketing, and data analysis. Preview with live token count for GPT-4o, Claude, and Gemini.

How do I use AI Prompt Builder?

1

Browse templates by category (Coding, Writing, Marketing, Data Analysis, etc.).

2

Click a template to open it in the customizer.

3

Fill in the variable fields on the right — each placeholder is highlighted.

4

View the live preview below with estimated token count for GPT-4o / Claude / Gemini.

5

Click Copy Final Prompt and paste directly into any AI chat interface.

What features does AI Prompt Builder offer?

10 hand-written prompt templates across 7 categories

{{variable}} placeholder system for customizable prompts

Live token count estimation via BPE heuristics

Category filter and keyword search across all templates

100% client-side — no account, no API calls required

Frequently Asked Questions about AI Prompt Builder

Does this tool call any AI API?

No. The Prompt Builder is a pure template engine — it builds and previews prompts locally in your browser. No API calls are made to OpenAI, Anthropic, or Google. Copy the prompt and paste it into your AI tool of choice.

How are token counts estimated?

Token counts use BPE (Byte-Pair Encoding) heuristics shared with the JoyTools Token Counter — approximately 1 token per 4 characters for English text. Actual token counts may vary ±5% depending on the model's tokenizer.

Can I add my own custom prompts?

Custom prompt templates are planned for a future release. Currently 10 hand-written templates are available, covering coding, writing, marketing, data analysis, image generation, business, and education use cases.

What prompt engineering frameworks do the templates follow?

The templates follow the CRAFT framework (Context, Role, Action, Format, Tone). This structure produces consistent, model-agnostic output that works well across ChatGPT, Claude, and Gemini without significant reworking.