Layer Height Calculator (Magic Numbers)

What Are Magic Numbers in 3D Printing?

"Magic numbers" are layer heights that are exact multiples of your stepper motor's full step resolution. When you use these values, the Z-axis motor lands precisely on full-step positions, eliminating micro-stepping inaccuracies and producing smoother, more consistent layers.

Why Does This Matter?

Most 3D printers use stepper motors with a 1.8° step angle and a lead screw with an 8mm lead (2mm pitch × 4 starts). This gives a full step height of 0.04mm. Layer heights that are multiples of 0.04mm (like 0.08, 0.12, 0.16, 0.20) will print more accurately than arbitrary heights like 0.15 or 0.25.

How to Calculate

The formula is: Full Step Height = Lead Distance ÷ (Steps per Revolution × Microstepping)

Where Lead Distance = Pitch × Number of Starts

Common Configurations

• Ender 3 / Most Creality: 1.8° motor, T8 lead screw (8mm lead) → 0.04mm step → magic numbers: 0.04, 0.08, 0.12, 0.16, 0.20, 0.24, 0.28, 0.32
• Prusa MK3/MK4: 1.8° motor, T8 lead screw → same 0.04mm step heights
• Voron (with 0.9° motors): Different magic numbers due to finer step resolution