Utilities
Handy utilities for everyday tasks and quick conversions
Essential utilities for day-to-day tasks. Generate QR codes for sharing, convert colors between formats, and convert measurement units. Simple, fast, and always free.
All Utilities
QR Code Generator
Create QR codes for URLs, text, and more. Customize size and colors. Download PNG.
Color Picker & Converter
Convert HEX, RGB, HSL, and CMYK. Check WCAG contrast between two colors.
Unit Converter
Convert length, mass, temperature, volume, area, data storage, and speed using convert-units. locally in your browser.
Percentage Calculator
Calculate percentages with seven modes: percent of, what percent of, increase/decrease, add/subtract percent, and percent difference
Color Contrast Checker
Check WCAG 2.1 AA and AAA color contrast ratios for text and UI components, with live preview and accessible color suggestions
What is in Utilities
The small things that do not belong anywhere else and get looked up constantly: generating a QR code, converting a color between HEX, RGB, HSL and CMYK, checking a color pair against the WCAG contrast thresholds, and converting units across length, mass, temperature, volume, area, data and speed.
The contrast checker is the one worth knowing about. Insufficient contrast is the most common accessibility failure on the web, and it affects far more people than most teams assume: anyone with low vision, most readers over sixty, and everyone using a laptop outdoors.
Nothing here needs an account and nothing is stored between visits.
The QR generator is worth a mention for what it does not do: there is no tracking redirect in the middle, so the code points straight at whatever you typed and will keep working after this site is gone. Codes from many free generators stop working when the middleman does.
Common questions
What contrast ratio do I actually need?
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WCAG AA asks for 4.5 to 1 on normal text and 3 to 1 on large text or user interface components. AAA raises normal text to 7 to 1. The checker reports the ratio and which thresholds it clears, for both text sizes at once.
Are the QR codes free to use commercially?
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Yes. The code is generated in your browser from the text you enter, there is no tracking redirect in the middle, and the resulting image is yours to use anywhere.
How precise is the unit converter?
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It uses exact conversion factors where they are defined, such as one inch being 25.4 millimetres, and full double precision arithmetic throughout, so rounding appears only in how the result is displayed.