12 free tools

Free unit, number, CSS, color, and contrast converters

Convert measurement units, number bases, Roman numerals, CSS sizing values, fluid clamp formulas, color formats, palettes, gradients, box shadows, grid and flexbox layouts, and contrast ratios with copy-ready browser outputs.

Best for quick measurement cleanup, binary and hex conversion, Roman numeral lookup, frontend sizing, fluid typography, responsive spacing, design token work, CSS color conversion, palette generation, grid and flexbox CSS, gradient and shadow generation, and WCAG color checks.

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Category

Converters

Access

Free

Browser-first utility pages

Each listed tool has its own page with focused controls, examples, assumptions, FAQs, and related tools.

Quick answer

Free unit, number, CSS, color, and contrast converters group related browser tools for one practical workflow.

Open an individual tool page when you need the actual controls, examples, assumptions, FAQs, and related links.

Best inputs

Start with the tool whose title most closely matches the job or output you need.

Use the tool descriptions and notes to decide whether you need a calculator, converter, formatter, generator, or planning helper.

If the workflow branches, use the related tools on each tool page to move to the next step.

Common use cases

This category helps you compare related tools and return to common tasks.

Compare related tools, open the most specific utility for your job, and move between adjacent tasks.

Use this category page as the index; use individual tool pages for task completion.

Common searches in this category

Use these task phrases when you know what you need but not the exact tool name.

Available now

Converters

Free · Live

Contrast Checker

Check foreground and background color contrast ratios with WCAG AA and AAA pass indicators.

WCAG color check

Free · Live

CSS Box Shadow Generator

Design CSS box shadows with offset, blur, spread, opacity, inset mode, preview, and copy-ready CSS.

Shadow CSS

Free · Live

CSS Gradient Generator

Create linear CSS gradients with color stops, angle controls, preview, and copy-ready CSS.

CSS gradients

Free · Live

Color Palette Generator

Generate tints, shades, complement colors, swatches, and copy-ready CSS variables from a HEX color directly in your browser.

Color tokens

Free · Live

CSS Clamp Generator

Generate responsive CSS clamp() formulas for fluid font sizes, spacing, and layout values from viewport ranges.

Fluid CSS sizing

Free · Live

CSS Grid Generator

Generate responsive CSS grid code locally with columns, rows, minmax column width, gap controls, live preview, and copy-ready CSS.

Grid layout CSS

Free · Live

Flexbox Generator

Generate flexbox CSS locally with direction, justify-content, align-items, flex-wrap, gap controls, preview, and copy-ready code.

Flex layout CSS

Free · Live

Unit Converter

Convert length, weight, temperature, data size, area, and volume units directly in your browser.

Measurement cleanup

Free · Live

CSS Unit Converter

Convert px, rem, em, and percent values for responsive CSS using root and parent font sizes.

Frontend sizing

Free · Live

Color Converter

Convert HEX, RGB, and HSL color values with a live preview and copy-ready CSS formats.

Design tokens

Free · Live

Number Base Converter

Convert integers between binary, octal, decimal, and hexadecimal locally in your browser.

Binary and hex

Free · Live

Roman Numeral Converter

Convert decimal numbers to Roman numerals and validate Roman numeral input locally.

Roman numerals

Why this category exists

This page groups related tools for easier browsing, while every individual tool page focuses on the specific workflow and output.

Frequently asked questions

Which conversions are supported?

This category includes everyday units, binary/octal/decimal/hex number bases, Roman numerals, CSS px/rem/em/percent sizing, CSS clamp formulas for fluid type and spacing, HEX/RGB/HSL color formats, color palette generation, CSS grid generation, flexbox generation, CSS gradient generation, CSS box-shadow generation, and WCAG contrast checks.

Do converter results require an account?

No. The current converter tools are free and available directly in the browser.

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