Measure twice. Slice once.

Print settings

3D Print Line Width Calculator

Translate a nozzle size and chosen ratio into a line-width target—also called extrusion width—then carry that value into wall and volumetric-flow checks.

Inputs

Use your slicer and nozzle guidance as the authority.
This is a simple adjacent-line preview; variable-width slicing and gap fill can change the final wall.

How the calculation works

Line width = nozzle diameter × width ratio. Approximate wall thickness = line width × perimeter count.

Interpret the line-width target

Enter the calculated millimeter value in the relevant line-width or extrusion-width field in your slicer. A slicer may use separate widths for external walls, internal walls, infill, supports, and the first layer, so apply the target to the feature you are evaluating instead of assuming one value controls every path.

Use the result in the next decision

For a CAD wall or shell, pass this line width to the Wall Thickness Calculator to choose a whole perimeter count. For a speed check, combine it with layer height and print speed in the Volumetric Flow Calculator. This sequence keeps wall geometry separate from the hotend flow limit.

Worked example

A 0.4 mm nozzle at 112% targets a 0.448 mm extrusion line. Three simple adjacent lines preview a 1.344 mm wall; use 0.448 mm as the input for the next wall or flow calculation rather than substituting the 0.4 mm nozzle diameter.

Assumptions and limitations

The arithmetic converts a requested ratio into a slicer target; it does not prove that the printer deposits that exact width. Material, temperature, speed, flow calibration, feature type, and adaptive-width behavior can change the printed result. Confirm the final path in slicer preview and validate critical dimensions with a representative print.

Related line-width decisions