Free Design Tools
Free design tools for picking colours, generating palettes and gradients, checking WCAG contrast, building CSS shadows and border-radius, and calculating aspect ratios.
Choose a tool and get an instant result
BlinkCalc tools are designed to be fast, practical, privacy-conscious, and easy to understand. Every result is calculated in your browser.
Aspect Ratio Calculator
Calculate and lock aspect ratios for images, videos, and screens.
Box Shadow Generator
Create and preview CSS box-shadow values visually.
Color Code Converter
Convert colors between HEX, RGB, HSL, and HSV formats instantly.
Color Contrast Checker
Check WCAG color contrast ratios for accessible web design.
Color Palette Generator
Generate random color palettes of 3–10 colors.
Color Picker
Pick any colour and convert it between HEX, RGB, and HSL formats.
CSS Border Radius Generator
Visually build CSS border-radius values and copy the CSS code.
CSS Gradient Generator
Build beautiful linear and radial CSS gradients visually.
Pixel Converter
Convert between px, rem, em, pt, and vw/vh CSS units.
Random Color Generator
Generate random HEX, RGB, and HSL color values.
Screen Resolution Checker
Instantly see your screen resolution, viewport size, device pixel ratio, and orientation.
Screen Size Calculator
Calculate diagonal screen size and PPI from width and height in pixels.
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Frequently asked questions
Can I use these CSS gradients and shadows commercially?
Yes. The CSS generated by our gradient, shadow, and border-radius tools is plain CSS. Copy and paste into any project, personal or commercial.
Are the contrast ratios WCAG-accurate?
Yes. The contrast checker follows the WCAG 2.1 formula and reports AA and AAA pass/fail for normal and large text.
Do you support HSL and HSV colour formats?
Yes. The colour picker and converter handle HEX, RGB, HSL, and HSV, and the palette tools export in any of those formats.