Color Converter (HEX/RGB/HSL)
Convert between HEX, RGB, HSL, and CMYK colour formats instantly. Includes a visual colour picker and CSS-ready output.
Create Visual Work with The Designer's Knife
Nine design tools plus a live showroom — offline and always ready
You need to create visual work. Design and brainstorm tools. The Designer's Knife delivers 9 purpose-built tools in a single HTML file.
The Designer's Knife puts nine essential design utilities plus a live preview Showroom into a single HTML file. Convert between color formats, check WCAG contrast compliance, build harmonious palettes, generate CSS gradients (linear, radial, conic), edit Bézier curves visually, build typographic scales from modular ratios, calculate spacing systems (linear, powers, Fibonacci), paint pixel art on a grid, and preview everything together in the Showroom — a live component gallery that renders your design system as buttons, cards, and typography in real time. All offline, all private, all yours forever.
WHAT'S INSIDE
9 tools in a single HTML file
WCAG Contrast Checker
Test foreground/background colour pairs against WCAG 2.1 AA and AAA contrast requirements. See pass/fail for normal and large text.
Palette Builder
Generate harmonious colour palettes — complementary, analogous, triadic, split-complementary, monochromatic, and tetradic — from any starting colour.
Gradient Generator
Build linear, radial, and conic CSS gradients visually. Add colour stops, adjust angles, and copy the CSS with one click.
HOW IT WORKS
Three steps. No setup.
1
Download the file
Purchase The Designer's Knife and download a single HTML file. No installer, no account, no setup.
2
Open in any browser
Double-click to open in Chrome, Firefox, Safari, or Edge. Works on any operating system.
3
Start working
Your data stays in your browser's local storage. Nothing is uploaded. Ever.
COMPLIANCE & GEOGRAPHY
Global
Works in any country. No server dependency, no regional restrictions.
FAQ
Frequently Asked Questions
How does The Designer's Knife help me create visual work?
The Designer's Knife provides 9 interconnected tools for design and brainstorm tools. Color converter, WCAG contrast checker, palette builder, gradient generator, Bézier editor, type scale, spacing calculator, pixel grid painter, and a live Showroom that previews your entire design system. Your design toolkit in one file.
Do I need an internet connection to create visual work with The Designer's Knife?
No. The Designer's Knife runs entirely in your browser as a single HTML file. All 9 tools work offline.
What is the difference between The Designer's Knife and cloud-based alternatives?
Cloud tools store your data on external servers, require subscriptions, and stop working without internet. The Designer's Knife is a one-time purchase ($39) that runs locally. Your data never leaves your device.
Can I use The Designer's Knife on multiple devices?
Yes. Once purchased, you can use The Designer's Knife on any device with a web browser. Copy the HTML file to as many devices as you need.
No cloud One fileOne-time purchase
Get The Designer's Knife — $39Sovereignty as a Service