Filament Length ↔ Weight Converter
Your slicer says 12.4 m, your scale says 38 g — this converts between them for any material and diameter. Also tells you how many metres are on a full spool.
How it's calculated
cross-section = π × (diameter / 2)² (1.75 mm → 2.405 mm²) grams = length (mm) × cross-section × density / 1000 metres = grams / density × 1000 / cross-section / 1000
- A strand of filament is a long cylinder, so mass = length × cross-sectional area × density.
- Density comes from our filament table (PLA 1.24 g/cm³, PETG 1.27, ABS 1.04, TPU 1.21…). Pick “custom” to type a figure from your spool's datasheet.
- Real filament has a diameter tolerance of about ±0.02 mm, which changes mass by roughly ±2%. Carbon- and wood-filled filaments vary more.
Questions people ask
How many metres of filament are in a 1 kg spool?
For 1.75 mm PLA about 335 m; PETG about 327 m; ABS about 400 m; TPU about 343 m. For 2.85 mm filament divide by 2.65.
How much does 1 metre of 1.75 mm PLA weigh?
About 2.98 g. PETG is 3.05 g, ABS 2.50 g, ASA 2.57 g and TPU 2.91 g per metre.
Why does my slicer show both grams and metres?
The slicer calculates the extruded volume and converts it with the density you set in the filament profile. If that density is wrong, the grams are wrong — the metres are the more reliable number.