Sandbox AI

Experiment with prompts and policies safely before production.

Free browser tools and guides — no account, no API keys, works on static hosting.

Built for practitioners

Everything runs client-side after the page loads. Ideal for Cloudflare Pages or any static host.

Tools

Assemble system and user messages with live token estimates and exportable JSON.

Preview regex-based redaction for emails, phones, keys, and card-like patterns.

Test prompts against length limits, blocked topics, and system preamble rules.

Preview markdown, extract code blocks, and validate JSON in model output.