Spool Scale.

3D Printing Filament & Tare Calculator · will it finish your print?

Empty Spool Tare & Brand Preset

Scale Gross Weight

Weight of spool + plastic on digital scale (g)

Filament Material

Density used to calculate remaining length

Net Filament Remaining

400 g
~134 m
40% of standard 1kg spool

Print Job Safety Check (Slicer Estimate)

Grams required by slicer (Bambu Studio / Orca / Cura / PrusaSlicer):
Enter your sliced model's required filament weight above to verify if your spool will finish the job.

How to calculate remaining 3D printing filament on a spool

To find out how much plastic is left on a spool without unwinding it, put the entire spool on a digital kitchen scale. Subtract the empty weight (tare) of the manufacturer's spool from the scale reading: Net Filament = Gross Scale Weight – Empty Spool Tare.

Why do empty spool tare weights vary?

Plastic injection-molded spools typically weigh between 220g and 260g (e.g. Bambu Lab reusable spool weighs ~250g, eSun weighs ~220g). Eco-friendly cardboard spools from Polymaker or Overture weigh significantly less, around 140g to 170g. Using the correct tare prevents throwing away good filament or suffering failed prints.

How to convert filament grams to remaining length in meters?

Standard 1.75mm filament has a volume of approx 2.405 cm³ per meter. Using standard PLA density (1.24 g/cm³), 1 meter weighs approx 2.98g (~335 meters per full 1kg spool). For PETG (1.27 g/cm³), 1 meter weighs approx 3.05g (~327 meters per kg).