Fired up by the success of my German standard page/standard line calculator (see below), I thought I’d knock out another calculation tool website.
But this time, a converter rather than a calculator. Because that will be loads quicker to implement. Won’t it?
Nope.
It’s way more complicated. If using maths, you build in the calculation formula and only ever have one correct answer. But for a converter you need a clear data model that’s able to compare data and round it where necessary.
Added to that, some shoe size systems have separate children’s sizes that partially overlap those for adults, as well as different sizes for women and men.
And because the website is in English and German, I had to localise not just the text on the page, but also the conversion function, to take into account the different decimal separators in the respective language regions.
Phew!
A quick website to fill a gap in my schedule became a mammoth project that took several weeks.
Published October 2025.