There are 333 meters in 1kg of standard 1.75mm PLA filament (varies by diameter).

A 1kg spool of 3D printing filament typically contains 200-400 meters, depending on diameter and material density. For 1.75mm PLA, expect ~333m; 2.85mm PLA yields ~125m. Filament length is calculated using volume, density, and cross-sectional area.

How Filament Length Is Calculated

  • Formula: Length (m) = (1,000g / density) / (π × radius²)
  • Key variables:
    • Filament diameter (1.75mm or 2.85mm most common)
    • Material density (PLA: ~1.24g/cm³; PETG: ~1.27g/cm³; ABS: ~1.04g/cm³)
  • Note: Tolerances (±0.05mm) and spool packing affect actual length.

Meters per Kilogram by Filament Type

Material Diameter (mm) Density (g/cm³) Meters in 1kg
PLA 1.75 1.24 ~333m
PLA 2.85 1.24 ~125m
PETG 1.75 1.27 ~328m
ABS 1.75 1.04 ~400m
TPU (Flexible) 1.75 1.21 ~344m

How to Verify Your Filament Length

  1. Weigh the spool: Subtract empty spool weight from total.
  2. Measure diameter: Use calipers (3 points along filament).
  3. Check density: Refer to manufacturer specs (varies by brand).
  4. Use a calculator: Input values into a filament length calculator.

Factors That Reduce Usable Filament

  • Spool tangles: Knots or overlaps waste 5-20m per spool.
  • Moisture absorption: Degrades material, requiring trimming.
  • End-of-spool thinning: Diameter may vary near the core.
  • Print failures: Failed prints consume filament without output.

Quick Conversion Cheat Sheet

  • 1.75mm PLA: 1kg ≈ 333m | 0.5kg ≈ 166m | 0.25kg ≈ 83m
  • 2.85mm PLA: 1kg ≈ 125m | 0.5kg ≈ 62m | 0.25kg ≈ 31m
  • ABS (1.75mm): 1kg ≈ 400m (lightest common filament)