# Services from css-design-calc.x402tookit.com on Zero

> css-design-calc.x402tookit.com serves 12 paid API services for AI agents, indexed by Zero. Each is callable per call with payment handled by Zero.

Canonical page: https://www.zero.xyz/host/css-design-calc.x402tookit.com
Live health (JSON, refreshed every minute): https://www.zero.xyz/host/css-design-calc.x402tookit.com/health.json

## Services

- [CSS Design Calc – Line Length Readability](https://www.zero.xyz/c/css-design-calc-line-length-readability-dce81b74/llms.txt): $0.02/call via x402. Estimates characters per line from column width and font size, then rates the result against WCAG readability guidelines (45–75 ideal, max 80).
- [CSS Design Calc – Fluid Clamp Generator](https://www.zero.xyz/c/css-design-calc-fluid-clamp-generator-73b8c208/llms.txt): $0.02/call via x402. Generates a CSS clamp() expression that linearly scales a size between a minimum and maximum viewport width, returning the slope, intercept, and rem values.
- [CSS Design Calc – CSS Unit Converter](https://www.zero.xyz/c/css-design-calc-css-unit-converter-f9d1770d/llms.txt): $0.02/call via x402. Converts a CSS length value from one unit to another (px, rem, em, pt, pc, in, cm, mm, Q, vw, vh, vmin, vmax, %) using configurable root and viewport sizes.
- [CSS Design Calc – Vertical Rhythm / Baseline Grid Snapper](https://www.zero.xyz/c/css-design-calc-vertical-rhythm-baseline-grid-snapper-ede4aaaf/llms.txt): $0.02/call via x402. Snaps multiple font sizes to a baseline grid, returning unitless line-heights, baseline lines, and margins for each size in both px and rem.
- [CSS Design Calc – Modular Type Scale](https://www.zero.xyz/c/css-design-calc-modular-type-scale-dbd4e560/llms.txt): $0.02/call via x402. Generates a modular type scale with px and rem values for steps above and below a base font size, using named or numeric ratios.
- [CSS Design Calc – WCAG 2.2 Target Size Checker](https://www.zero.xyz/c/css-design-calc-wcag-2-2-target-size-checker-6ce04d01/llms.txt): $0.02/call via x402. Validates a click/touch target's dimensions against WCAG 2.2 AA (24 px) and AAA (44 px) target size criteria, including the spacing exception for nearby undersized targets.
- [CSS Design Calc – Pixel Density Calculator](https://www.zero.xyz/c/css-design-calc-pixel-density-calculator-28e74866/llms.txt): $0.02/call via x402. Computes screen PPI, physical dimensions, CSS viewport size, dot pitch, and image widths for a given screen resolution and diagonal.
- [CSS Design Calc – Grid Column Width Calculator](https://www.zero.xyz/c/css-design-calc-grid-column-width-calculator-285e7c7a/llms.txt): $0.02/call via x402. Calculates column widths and span widths for an N-column grid from container width, column count, and gutter size — or reverse-calculates the container width from a known column width.
- [CSS Design Calc – Golden Ratio Splitter](https://www.zero.xyz/c/css-design-calc-golden-ratio-splitter-fc14849c/llms.txt): $0.02/call via x402. Splits a total length into major and minor parts using the golden ratio (or silver, root-2, root-3, root-5, thirds, or a custom ratio), returning both values, percentages, and matching CSS grid columns.
- [CSS Design Calc – Box Model Size Calculator](https://www.zero.xyz/c/css-design-calc-box-model-size-calculator-68e3c1a4/llms.txt): $0.02/call via x402. Calculates all CSS box model dimensions (content, padding, border, and margin boxes) from a given width and height under content-box or border-box sizing
- [CSS Design Calc – Aspect Ratio Calculator](https://www.zero.xyz/c/css-design-calc-aspect-ratio-calculator-f7d0decf/llms.txt): $0.02/call via x402. Calculates the simplified aspect ratio of a width/height pair, or derives the missing dimension from a known ratio, and returns CSS-ready values including css-aspect-ratio and padding-top percent.
- [CSS Selector Specificity Calculator](https://www.zero.xyz/c/css-selector-specificity-calculator-06a6ab50/llms.txt): $0.02/call via x402. Calculates CSS selector specificity (IDs, classes, types) per Selectors Level 4, including :is(), :not(), :where(), and :has(), and optionally compares two selectors to determine which wins in the cascade.

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