How to check how much filament is left
- Put the spool on a kitchen or postal scale, filament and all.
- Subtract the weight of an empty spool of the same brand and size. Keep one empty spool of each brand you use and write its weight on it.
- The difference is the filament left. The calculator also converts it to meters using the material's density.
Will my print fit on what's left?
Enter the filament weight your slicer reports for the print. Leave yourself a margin of at least 5%: slicer estimates are not perfect, and the last few meters near the hub can tangle or be unusable.
Tips
- Spool weights vary a lot between brands and between plastic and cardboard spools, so don't rely on a single "average" value.
- For an almost empty spool, a long print can be split across two spools with a filament change (
M600) at a chosen layer.
Frequently asked questions
How much does an empty filament spool weigh?
It depends on the brand and material. Empty 1 kg spools commonly weigh somewhere between about 130 and 250 g. Weigh an empty one from the same brand for an accurate number.
How many meters of filament are left on my spool?
Weigh the spool, subtract the empty spool weight and enter both above. For 1.75 mm PLA, each gram is about 0.34 m.