SVGs also carry a preferred output size where you do have pixel-perfect control. It is a bit messy, though, as you need to position lines on half-pixels so that

SVGs also carry a preferred output size where you do have pixel-perfect control. It is a bit messy, though, as you need to position lines on half-pixels so that a line with width 1 will not fall on two pixels. I tend to prefer paths when working with pixel-perfect data for that reason. Some icons can be smaller than their PNG equivalent (even more so when served compressed) but that mainly depends a bit on how they're authored. Many authors probably just use Inkscape/Illustrator and accept the 20 KiB of cruft that is embedded automatically instead of writing a simple sub-1-KiB SVG by hand.