Color & CSS Tools
21 toolsWriting CSS for colors, gradients, and shadows by hand often means guessing values, refreshing the browser, and repeating the cycle until it looks right. These visual tools eliminate that trial-and-error loop entirely. Convert colors between HEX, RGB, and HSL formats to ensure consistency across your design system; generate linear and radial CSS gradients with interactive color stops and angle controls; build box shadows with adjustable offset, blur, spread, and opacity — all with an instant live preview that shows exactly how each property looks before you write a single line of CSS. The color palette generator creates harmonious color schemes (complementary, analogous, triadic) from any base color, giving you a complete palette with ready-to-use HEX, RGB, and HSL values for design tokens. The aspect ratio calculator helps you maintain proportional dimensions for responsive images, videos, and UI elements across breakpoints. Every tool outputs clean, copy-ready CSS code compatible with all modern browsers — no vendor prefixes required. Whether you are building a design system from scratch, fine-tuning a landing page, or exploring color options for a client project, these tools make the visual design process faster and more precise.
Color Tools 3 tools
Convert, build, and check color values and palettes.
Gradients & Effects 7 tools
Generate gradients, shadows, and modern surface effects.
Layout & Responsive 5 tools
Grid, flexbox, sizing, and responsive preview helpers.
CSS Generators & Utilities 6 tools
Produce ready-to-paste CSS for common patterns.
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Search all tools insteadCommon Use Cases
Convert brand colors between HEX, RGB, and HSL for design system documentation
Generate accessible color palettes for dark mode and light mode themes
Create CSS gradients for hero sections, buttons, and card backgrounds visually
Build consistent box shadow scales (sm, md, lg, xl) for elevation design tokens
Calculate responsive image dimensions that maintain correct aspect ratios
Prototype CSS animations with custom timing functions and keyframe previews
Generate clip-path shapes for creative section dividers and image masks
Frequently Asked Questions
Do the generated CSS values work in all modern browsers?
Yes. All generated CSS uses standard syntax supported by Chrome, Firefox, Safari, and Edge. No vendor prefixes are needed for the properties used by these tools in current browser versions.
Can I use these tools for design work outside of CSS?
Yes. The color converter and palette generator output HEX, RGB, and HSL values that work in any design tool including Figma, Sketch, and Adobe Creative Suite. The visual interfaces are useful for exploring color and layout options regardless of your output format.
How do I ensure my color choices meet accessibility standards?
Use the color converter to obtain RGB values, then calculate the WCAG contrast ratio between your text and background colors. WCAG 2.1 requires a minimum 4.5:1 ratio for normal text and 3:1 for large text. Avoid relying solely on color to convey information.
What is the difference between HEX, RGB, and HSL color formats?
HEX (#FF5733) is a compact hexadecimal notation widely used in web development and design handoff. RGB (rgb(255, 87, 51)) defines color by red, green, and blue channel values from 0 to 255 — it maps directly to how screens display color. HSL (hsl(11, 100%, 60%)) defines color by hue (color wheel degree), saturation (vibrancy), and lightness (brightness) — it is the most intuitive for humans to adjust because you can shift the hue without affecting brightness, or desaturate without changing the color itself. Use HEX for concise CSS code, RGB for programmatic color manipulation, and HSL when you need to create tints, shades, or harmonious variations of a color.
How do I create a consistent design system with these tools?
Start by choosing a primary brand color and use the Color Palette Generator to create a harmonious palette with complementary, analogous, or triadic colors. Then use the Color Converter to define each color in HEX, RGB, and HSL formats for your CSS custom properties (design tokens). For elevation and depth, use the Box Shadow Generator to create a consistent shadow scale (sm, md, lg, xl). Finally, define your gradient system with the Gradient Generator. Export all values as CSS custom properties for a single source of truth across your project.
Why do gradients sometimes look muddy or gray in the middle?
This happens because CSS gradients interpolate colors in the sRGB color space by default, which is not perceptually uniform. A red-to-blue gradient passes through a grayish midtone in sRGB but produces a vibrant purple in perceptually uniform color spaces. Modern CSS supports color space specification: linear-gradient(in oklch, red, blue) produces much more vibrant results. Chrome 111+ and Safari 16.2+ support this syntax. Use these tools to define your base colors, then specify the interpolation color space in your CSS for optimal results.
What common aspect ratios should I know for web and mobile?
16:9 is the standard for HD/4K video, desktop monitors, and YouTube thumbnails. 4:3 is the classic format still used in some tablets and presentations. 1:1 (square) is used for social media profile pictures and Instagram posts. 9:16 (portrait) is the standard for mobile-first video content like Instagram Reels, TikTok, and YouTube Shorts. 1.91:1 (1200×628) is the recommended Open Graph image ratio for optimal display on Facebook and LinkedIn link previews. The Aspect Ratio Calculator helps you compute missing dimensions for any ratio.
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