A free WebP / AVIF / PNG / JPEG image converter tool that runs entirely in your browser. Convert images quickly while protecting your privacy, without uploading them to a server. Supports quality adjustment, bulk download, Before/After comparison slider, and Base64 export.

Simulate OGP display in real-time for major social media platforms like X (Twitter), Facebook, LINE, Slack, and Discord. Includes safe area guides and Next.js Metadata code generation. The ultimate OGP simulator to ensure pixel-perfect display before publishing.

A command center tool for text size design that supports building responsive design systems. Provides all necessary features for text size design, including PX⇔REM conversion, Visual Ruler, Tailwind Suggestion, Modular Scale, and Fluid Typography (clamp function) generation.

Simply paste JSON to generate TypeScript types, Zod schemas, and mock data in bulk. Includes Smart Inference functionality that intelligently infers values and key names (automatic detection of dates, Emails, URLs). Supports real-time conversion and JSON formatter.

Generates layered shadows, glassmorphism, and neumorphism based on physics calculations. Includes presets inspired by Stripe, Vercel, and macOS, dynamic backgrounds, and comparison features. Outputs in CSS/Tailwind JIT/Tailwind Config format.

A background design tool that allows intuitive GUI operation to create aurora (Mesh Gradient) and noise textures, essential for modern web design. Supports drag operations utilizing Framer Motion, Linear/Radial Gradient, Non-linear Easing functionality, and SVG Noise Overlay. Includes CSS code generation and PNG export features.

Intuitively generates "intellectual and deep web backgrounds" adopted by Vercel and Linear, among others. Includes 6 types of patterns like Grid, Dots, Graph Paper, Smart Masking (Vignette/Fade), Texture & Noise, and Interactive Spotlight features. Outputs in CSS/Tailwind/React Component format.

A fee calculation tool fully adapted for Japanese freelance work. Supports both General (hourly rate/fixed fee) and SES (billing range) modes. Includes Invoice System compliance, withholding tax calculation, crowdsourcing fee calculation (rate/fixed amount), automatic business day calculation, and annual income conversion features. Exportable in Email/Excel/Notion formats.