5 Free Client-Side Developer Micro-Tools Every Engineer Should Bookmark in 2026
When building micro-SaaS and AI-assisted workflows, small developer utilities save hours of repetitive typing. We built and open-sourced 5 client-side, zero-telemetry web utilities that execute 100% in your local browser memory:
- JSON to TypeScript & Zod Schema Converter: Instantly transforms raw JSON API payloads into strict TypeScript interfaces and runtime Zod validation schemas.
- Cron Expression Visualizer & Schedule Explainer: Translates 5-field cron syntax into plain English schedules for GitHub Actions and serverless workers.
- 2026 LLM Token & Cost Estimator: Compare prompt token counts and monthly API costs across Gemini, GPT, Claude, and DeepSeek.
- Stripe vs. PayPal vs. Gumroad Net Payout Calculator: Calculate exact creator take-home margins after MoR and payment gateway fees.
- SVG to CSS Data URI & Tailwind Arbitrary Value Encoder: Convert SVG icons into compact UTF-8 Data URIs ready for Tailwind classes.
👉 Live Tools Portal: https://wlegend369.github.io/free-developer-tools-suite/
👉 GitHub Source Code: https://github.com/Wlegend369/free-developer-tools-suite
100% open-source, client-side only, zero tracking.
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