Yardage from weight

My yarn does not have the yardage on it… but its a 76g (leftovers from another project - I weighed it)…

is there any way to determine the yardage from the weight?

I hope I have enough yardage for my project, but I don’t want to end up a few rows to short!

Sure, if you know how much is in a skein of it and what the yardage is for a skein then figure it out from there. Divide the yards by gms then multiply by 76.

You could measure out 5-10 yds of the yarn and weigh that, then multiply 76gms times the yards you measured out and divide by the number of grams the measured yds weigh
That’ll give you an estimate of how many yds you have.