Converting pixels to cm?

[wakecarter]

I wouldn’t recommend assuming the size of the monitor in pixels. Have you tried the screen scale demo?

https://run.pavlovia.org/Wake/screenscale/

Here are some threads which might help.

How to use screen scale routine

Hello, I’m trying to build an online experiment and I need to adjust the resolution for every participant individually. I’m using screen scale routine (this one: Pavlovia), but the resolution doesn’t seem to change after this routine. I’ve tried inserting code component in other routine which contains an image (the code is: expInfo[‘Window_size’] = [x_scale, y_scale]), but the image size is not changing. I suppose I’m doing something wrong, how could this be solved?

Consistent image size across screens

URL of experiment: https://run.pavlovia.org/aelreym/concurrent_schedule_task/html Description of the problem: In the routine “cigarette length” I ask participants to estimate the real length of a cigarette by clicking on the appropriate image. So I have images of cigarettes with the real length of cigarettes and some deviations. In my builder experiment I have set the units of my images to “cm” but this doesn’t work online. I have changed it to “from exp settings” and this does adapt the size…

Way to get monitor information like size when running exp online?

Description of the problem: I am trying to figure out how to get the monitor size of each participant that takes my study online and store it as a variable in my excel data files. How do I do this?