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CSS Pixel Converter Calculator
Convert px to rem or em in CSS. rem is preferred for responsive design, while px is used f...
Read MoreData Size Converter Calculator
Convert data sizes between B, KB, MB, GB, and TB using base 1024.
Read MoreAspect Ratio Calculator
Enter width and height in pixels to get the aspect ratio (e.g. 16:9) reduced by the greate...
Read MoreHEX RGB Converter Calculator
Convert between HEX codes and RGB values — useful for CSS color work.
Read MoreDPI to Inches Calculator
Enter pixel dimensions and DPI to calculate the physical print size in inches.
Read MoreAbout This Category
Design and engineering teams mix units constantly: CSS pixels against device pixels, decimal against binary byte prefixes, aspect ratios against resolutions. Each conversion here is arithmetic plus the convention behind it.
The byte conversion is the one that causes the most confusion. Drive makers use 1 kB = 1,000 bytes; operating systems historically reported 1,024, which is why a drive sold as 1 TB shows about 931 GB in the file manager.
Frequently Asked Questions
Why does a 1 TB drive show 931 GB?
Because 10¹² bytes divided by 1,024³ is about 931. The manufacturer uses decimal prefixes; the operating system counts binary ones and labels them GB.
How do I keep a 16:9 layout on any screen?
Use aspect-ratio: 16 / 9 or padding-bottom: 56.25 %. Both derive from height ÷ width, which is 9 ÷ 16.
Is a CSS pixel a physical pixel?
No. CSS assumes 96 pixels per inch and the browser scales that to the device, which is why 16 px text looks the same on screens with very different densities.
Calculators in This Category
Sources & last update
2026-10-19