3DPrintCalcs
Flow Rate Calculator — Volumetric Extrusion
Calculate volumetric flow rate from print speed, layer height and line width.
How We Calculate This
Formula
- Flow rate = Print speed x Layer height x Line width (mm³/s)
- Filament feed speed = Flow rate / Filament cross-section area
The filament feed speed tells you how fast the extruder gear must push the filament to achieve the desired flow rate.
Frequently Asked Questions
It is the volume of plastic extruded per second, measured in mm³/s. It determines how fast your hot end needs to melt filament. Most standard hot ends cap around 10-15 mm³/s.
Under-extrusion. The extruder cannot push filament fast enough through the melt zone, causing gaps, weak layers and potentially skipped steps on the extruder motor.
Print a volumetric flow test. Gradually increase speed while monitoring extrusion quality. The point where under-extrusion begins is your maximum volumetric flow rate.
Related Calculators
Nozzle Flow Rate Calculator
Calculate volumetric flow rate, maximum recommended print speed, extrusion width and filament feed speed from nozzle diameter, layer height and material.
Print Speed Calculator
Calculate maximum print speed based on volumetric flow rate and layer dimensions.
First Layer Calculator
Calculate optimal first layer height, width and speed for strong bed adhesion.
Wall Thickness Calculator
Calculate wall thickness from number of perimeters and nozzle/line width.
Print Time Estimator
Estimate total print time from layer count, speed and travel moves.
Was this calculator helpful?
Last updated: February 2026
All calculations are estimates. Always verify settings with test prints before committing to final prints.