Filament calculator
How many grams is that 18 m of PETG? How much is left on a half-used spool? Pick a material and diameter: the math is instant.
Weight → length
Enter a weight in grams.
Length → weight
Enter a length in meters.
How much is left on this spool?
Enter the spool's net weight.
Remaining can't be more than the spool weight.
Tip: most 1 kg spools list a net filament weight: weigh an empty spool once and subtract it for accuracy. Gyroid tracks all of this per spool. See what Gyroid does.
How much filament is on a 1 kg spool?
It depends on density and diameter as well as weight. A kilo of 1.75 mm PLA is about 335 m; the same kilo of PETG is about 327 m, and ABS about 400 m because it's the least dense of the common materials. In 2.85 mm the same kilo is roughly a third of the length, since the cross-section is about 2.65 times larger.
How much filament do I need for this print?
Your slicer reports a weight estimate after slicing. Use that, and add about 5% for the purge line, skirt, and the occasional restart. If all you have is a length, put it into the length → weight box above. For project-scale budgeting and typical part weights, see how much filament do I need.
How much is left on a partially used spool?
Weigh the whole spool and subtract the empty spool weight. Manufacturers often print that tare weight on the label. If not, weigh one you've finished. Cardboard cores tend to run 130-180 g and molded plastic 180-250 g. Get the number once per brand and the rest is arithmetic, which the box above will do for you.
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