AI Prompt Lab

Analyze, test, and optimize your LLM prompts.100% Client-Side. No data leaves your browser.

What is AI Prompt Lab?

A browser-based toolkit for developers and AI practitioners to write better prompts for LLMs. Every tool runs 100% in your browser — no server, no API key, no data sent anywhere.

Prompt Quality Checker

Score your prompt on clarity, structure, and completeness — get actionable fixes.

Mutation Generator

Generate phrasing variations to find the most effective wording.

Diff Viewer

Compare two prompt versions word-by-word to track changes.

Token Estimator

Estimate token count and API cost across major model pricing.

Stress Test

Run a prompt N times and measure how consistent the output is.

Workspace

Base Prompt

Press Cmd + Enter to generate

Prompt A

Prompt B

Paste your prompt or text

Prompt to Stress Test

Iterations

AI Prompt Lab

What is AI Prompt Lab?

Prompt Quality Checker

Prompt Mutation Generator

Prompt Diff Viewer

Token Estimator

Stress Test