Welcome fellow prototypers! This communities' purpose is to help others and share functional 3D Printing related information. While other 3D Printing Communities are a good resource, sometimes too many help posts get buried under memes and fluff. This will remain technically focused and keep the fluff removed. Please help your fellow 3D Printer hobbyists as much as you can with their issues! and showcase your functional prints and how you use or created them.
Not really.
You can weigh it, and the slicer gives you an estimate of how much volume/mass is needed.
But it's not too difficult to pause a print. Unload what little you have left and reload a new roll then resume the print.
That's assuming you have another roll of the exact type/color filament you are using ready to go.