How to re-calibrate my y axis its out by 11mm

Can anyone tell me how to re-calibrate my Y axis it is out by 11mm
i have put a grid on my wasteboard and in the location top right hand side my Y is saying 89.66
when on the board its on 100mm from last night this has happened i cant take screenshot to show you

Hi Marc,

Welcome to tha Forum. We have fun and games. :musical_notes:Welcome to tha forum, welcome to that forum. :musical_note:

Calibration tool, it’s baked into gsender as an additional feature. Read all about it here:

@marc What machine are you running? What controller? Do you have limit switches?
You say that this only started last night. What were you doing immediately before you noticed this?