Filament Remaining Calculator
Weigh a spool or enter the grams you have left. Estimate remaining filament percentage and length using your diameter and an approximate or custom density.
FROM WEIGHT TO LENGTH
A useful estimate before a long print.
Net grams = loaded spool weight − empty spool weight. In direct mode, enter net grams yourself. Percent remaining = net grams ÷ original net capacity × 100.
Length in meters = grams ÷ density in g/cm³ ÷ (π × (diameter in mm)² ÷ 4). This assumes solid, circular filament of uniform diameter. The volume and length conversion factors cancel. Diameter tolerance and density uncertainty affect the answer, so compare against your slicer's estimate with a practical reserve.
Example only: 750 g loaded minus a 250 g empty spool leaves 500 g. On a 1,000 g net spool, that is 50% remaining.
APPROXIMATE PRESETS
Use your material's density when known.
These are reference formulations, not universal densities. Manufacturer data was checked September 3, 2026 against Polymaker's technical data table ↗.
- PLA: approximately 1.23 g/cm³ (PolyLite PLA Pro).
- PETG: approximately 1.25 g/cm³ (PolyLite PETG).
- ABS: approximately 1.04 g/cm³ (PolyLite ABS).
- ASA: approximately 1.13 g/cm³ (Polymaker ASA).
- TPU: approximately 1.22 g/cm³ (PolyFlex TPU95).
Custom density is available for any brand, filled blend, flexible formulation or measured value. Empty-spool weight varies by spool and must be supplied.