Free Tools for Builders.
Every tool is completely free. No signup, no usage limits, no hidden fees. Built for developers who ship fast.
Stripe Fee Calculator
Calculate exact Stripe fees for any scenario — domestic, international, currency conversion, Connect fees, and dispute costs.
JSON Schema Forge
Paste JSON → get TypeScript types, Zod schemas, JSON Schema specs, OpenAPI definitions, and database migration SQL.
Cron Expression Builder
Visual cron job scheduler with human-readable output. Test expressions with a virtual timeline, export for Vercel, Railway, Render.
Color System Generator
Input a brand color → generate a full design token system. CSS variables, Tailwind config, accessible contrast pairs, and dark mode.
Webhook Debugger
Get a unique URL, send webhooks to it, inspect headers, body, and timing. Replay webhooks and share debug sessions.
API Response Mocker
Create mock API endpoints instantly. Define routes, response shapes, delays, and error rates. Get a live URL for frontend dev.
README Generator AI
Describe your project or paste a GitHub URL → get a professional README.md with badges, installation, API docs, and contributing guide.
SaaS Metrics Dashboard
Input MRR, churn, new customers → instantly see LTV, CAC ratio, quick ratio, growth rate, and net revenue retention. Exportable.
Startup Cost Estimator
Input your stack decisions (hosting, auth, email, payments, CDN) → get monthly and yearly cost projections. Compare cloud providers.
OG Image Generator
Create stunning Open Graph images for social media. Choose templates, customize colors, typography, and layout. Download as PNG.
Regex Tester & Explainer
Write, test, and debug regular expressions with real-time match highlighting, capture group inspection, and plain-English explanations.
Start Building Today
All tools are free to use. No account needed, no credit card, no limits. Just pick a tool and get to work.