// Utilities — Filament Spool Dimensions Guide

Spool Outer Diameter
Reference Guide

Outer diameter, width, and bore for 1kg, 500g, and 250g spools across 35+ brands. Filter by spool weight or multi-material system compatibility. Data sourced from manufacturer specs, onlyspoolz.com, and community measurements.

Bambu Lab AMS / AMS 2 Pro
OD: 197–202mm  |  Width: 50–68mm
A spool at 203–205mm sits proud and the lid won't latch. AMS Lite reads bore instead: needs 53–58mm bore, tolerates 40–68mm width. Cardboard spools need the Spool Adapter Ring.
Creality CFS (CFS-01 / Ender Multi)
OD: ≤200mm  |  Width: ≤68mm  |  Bore: 52–58mm
CFS uses a similar geometry window to AMS. Spools rated AMS-compatible are generally CFS-compatible. Verify width — CFS is slightly less tolerant of wide spools than AMS Lite.
Weight
Compat
—
Brands
—
AMS/CFS ✓
—
AMS/CFS !
—
AMS/CFS ✗
~200mm
Typical 1kg OD
AMS/CFS Compatible (197–202mm)
Marginal — may need adapter or varies by batch
Incompatible / proprietary
OD = outer diameter, flange edge to flange edge
Data notes: No ISO/ASTM standard governs filament spool geometry. The ~200mm outer diameter is a de-facto convention, not a published specification. Many brands change spool design between batches — treat all figures as typical/nominal. 500g and 250g data is significantly sparser than 1kg; entries marked ~approx are estimated from known spool families. 250g spools vary most — from 130mm mini-spools to full-size 200mm narrow shells. Sources: manufacturer datasheets, onlyspoolz.com, sigmafilament.com, Printables community tare-weight catalog, and product listings. Last updated June 2026.