Filament Length Calculator

Calculate how many metres of filament are on a spool by weight and material.

How many metres of filament are on a spool is one of those questions every 3D printer owner searches at least once. The answer depends on two things: the weight of the spool and the density of the material. A 1kg spool of PLA (density 1.24 g/cm³) at 1.75mm diameter gives you around 332 metres — enough for dozens of small prints. ABS is less dense so you get more length per kilogram (~396m/kg). PETG is denser so you get slightly less (~323m/kg). This calculator works for any spool weight and both 1.75mm and 2.85mm diameters.

335.3 metres

1,100 feet · 33,528 cm

Length by spool size (PLA, 1.75mm)

WeightLength
0.25kg84m
0.5kg168m
1kg335m
2kg671m

Filament length reference (1.75mm)

Material0.5kg1kg2kg
PLA166m332m665m
PLA+166m332m665m
PETG162m323m646m
ABS198m396m792m
TPU170m340m681m

FAQ

How many metres of filament in a 1kg PLA spool?

A standard 1kg spool of PLA at 1.75mm diameter contains approximately 332 metres of filament. This is based on PLA's density of 1.24 g/cm³. Budget spools sold as 1kg sometimes contain slightly less (950–980g) so actual length may vary by 5–10%.

How many metres of filament in a 1kg PETG spool?

A 1kg spool of PETG at 1.75mm contains approximately 323 metres. PETG has a slightly higher density than PLA (1.27 g/cm³) so you get marginally less length per kilogram.

Does filament diameter affect how many metres you get?

Yes significantly. 2.85mm diameter filament is much thicker — a 1kg PLA spool at 2.85mm gives around 125 metres vs 332 metres at 1.75mm. Most modern desktop printers use 1.75mm; 2.85mm is used by Ultimaker and some older Lulzbot printers.

How do I calculate filament length from weight?

Formula: Length (m) = Weight (g) / (density × π × (diameter/2)²) / 100. For 1kg PLA at 1.75mm: 1000 / (1.24 × π × 0.875²) / 100 = ~332m. This calculator does it instantly for any weight and material.

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