3D Filament Guide — Filament density, spool length, drying

Filament density, spool length, drying

3D Filament Guide
Independent · 2026

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Filament Density: Convert Spool Weight to Length

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Filament density reference

Density converts net filament weight into printable volume and length. These published values belong to the named grades; they are starting points for spool arithmetic, not averages for every product carrying the same material label.

Published filament densities in grams per cubic centimetre (g/cm³)
Material	Density (g/cm³)	Product and source
PLA	1.24	Prusament PLA
PETG	1.27	Prusament PETG
ABS	1.04	eSUN ABS (2024 product manual)
ASA	1.07	Prusament ASA
TPU	1.21	eSUN eTPU-95A (2024 product manual)
PC	1.20*	PolyLite PC (published range: 1.19–1.20)
CF-nylon	Grade dependent	eSUN ePA-CF: 1.24; ePAHT-CF: 1.40 (2024 manual)

*1.20 is the upper end of PolyLite PC's published range. Filled nylons have no single density: the two examples above use different grades. Use the current technical data sheet for your spool. The calculator's presets include other products, so replace its density field when using a figure from this table.

Filament weight and length calculator

Convert spool weight to remaining metres using material density, tare weight and filament diameter, with a density table for PLA, PETG, ABS, ASA, TPU and PC that cites each figure to a named product's data sheet and shows how far vendors disagree. Runs in the browser, no signup.