Spool Length Calculator

Calculate the total length of filament on a spool from its weight and diameter.

Filament Weight (g)

Diameter (mm)

Density (g/cm3)

How It Works

Enter the spool weight, filament diameter, and material density. The calculator divides the weight by the per-meter weight to find total filament length in meters.

Formula

Length (m) = Weight (g) / (PI x (diameter/2)^2 x density (g/cm3) x 100)

Frequently Asked Questions

How long is a 1kg spool of 1.75mm PLA?

A 1kg (1000g) spool of 1.75mm PLA (density 1.24 g/cm3) contains approximately 335 meters of filament.

Does spool weight include the spool itself?

No, enter only the filament weight. Weigh the full spool and subtract the empty spool weight (usually 200-250g).