Print an actual ruler to measure in pixels. Generated for your screen, truly.

Download Ruler PDF for dpi

Look up the dpi for your device here, e.g. iPhone 5 326 dpi, Macbook Pro Retina 221 dpi.

Support us! This is just a fun little idea, hastily implemented. Actually we build apps. Buy them. Send us a photo of your ruler. Follow us on Twitter.

Thanks Big respect goes to James Hall for jsPDF and Lea Verou for the initial inspiration by creating Fork us on Github.