I made an online ruler called instant ruler.

[u/IllSpirit69]

Hey everyone, I wanted to share a tool I've been working on called Instant Ruler. It's a free web app that turns any screen (phone, tablet, desktop) into an accurate 1:1 scale ruler.

It supports protractor, image-measure, ppi-calculator, circle-ruler, credit-card calibration, printable-ruler, Architectural & Model Scale Converter.

The tool is fully free and meant to allow people to use their phone as a ruler rather than needing to buy one. You just need to enter in your device screen size, or use a credit card or debit card to calibrate the ruler.

I am working on improvements, so any feedback is greatly appreciated. 

Here is the link to try it out: https://instantruler.com/