How to Gauge if there is enough Filament left for print?

[ONUS]

Can someone please give me a suggestion on how to gauge if there is enough printer filament left on a spool for a particular print I am about to make? What's the best method of doing this, as I don't want to leave the house and come back only to find out that I ran out of filament. Is there a measurement method, or do I have to weigh it and then know exactly how many grams my expected object will be when printed? I assume there has to be a way of going about this, but I can't for the life of me figure out what everyone else is doing. Any suggestions?

[Roxy]

Can someone please give me a suggestion on how to gauge if there is enough printer filament left on a spool for a particular print I am about to make? What's the best method of doing this, as I don't want to leave the house and come back only to find out that I ran out of filament. Is there a measurement method, or do I have to weigh it and then know exactly how many grams my expected object will be when printed? I assume there has to be a way of going about this, but I can't for the life of me figure out what everyone else is doing. Any suggestions?

I use Pronterface to print. When you load the GCode for a given print, it goes through every line of GCode and adds up how much plastic is going to get extracted. It will tell you the length. If there is any doubt in your mind, you can just unspool the plastic that is left and see how long it is.