Calibration Calculators
Klipper Rotation Distance Calculator
Use this Klipper rotation distance calculator to convert a measured extrusion test or known Marlin steps/mm into a manual printer.cfg rotation_distance update.
Quick answer
To recalibrate Klipper rotation_distance, multiply your current rotation_distance by the actual extruded length divided by the commanded length. For example, 7.5 × 95 ÷ 100 = 7.125 mm. Command a slow 100 mm extrusion, measure what actually moved, enter the three values below, then copy the new rotation_distance into printer.cfg.
Results update below from browser-local calculations.
Breakdown
| New rotation distance | 0 |
|---|---|
| Equivalent steps/mm | 0 |
| Rotation distance from steps/mm | 0 |
How to Use This Calculator
- Enter your current Klipper rotation_distance, command a measured extrusion move, and enter the actual filament movement.
- Use full steps, microsteps, and known Marlin steps/mm only when you want a reference conversion or equivalent steps/mm output.
- Copy the new rotation_distance into printer.cfg manually, then repeat the extrusion test if the correction is large.
Inputs and Assumptions
| Current rotation distance | Enter this value in mm. |
|---|---|
| Commanded extrusion | Enter this value in mm. |
| Actual extrusion | Enter this value in mm. |
| Full steps per rotation | Most 1.8 degree steppers use 200. Use 400 for many 0.9 degree steppers. |
| Microsteps | Enter this value in microsteps. |
| Known Marlin steps/mm | Optional helper for converting an old Marlin E-steps value to Klipper rotation_distance. |
Klipper rotation_distance example
If current rotation_distance is 7.5, commanded extrusion is 100 mm, and actual extrusion is 95 mm, the new rotation_distance is 7.125. With a 200-step motor and 16 microsteps, that is equivalent to about 449.12 steps/mm.
printer.cfg Example
After calculating the value, edit your Klipper config manually. PrintCostCalc only shows the number and never connects to Moonraker, Klipper, or your printer.
[extruder]
rotation_distance: 7.125Steps per mm Conversion
If you are moving from Marlin, enter the old steps/mm value in the optional helper field. The calculator uses full steps per rotation multiplied by microsteps, divided by steps/mm, to estimate the Klipper rotation_distance reference value.
Use the measured extrusion result as the final calibration check. Hardware reference values are useful starting points, but filament slip, gear geometry, and measurement error still matter.
Measure 100 mm Extrusion
- Heat the hotend to a safe printing temperature for the loaded filament.
- Mark the filament above the extruder, command a slow 100 mm extrusion, then measure the actual movement.
- Enter the current rotation_distance, commanded extrusion, and actual extrusion in the calculator.
- Repeat the test after editing printer.cfg if the change is large.
Rotation Distance vs E-steps
Marlin-style E-steps describe steps per millimeter. Klipper rotation_distance describes filament movement per motor rotation, so the relationship is inverse. If actual extrusion is low, the new rotation distance often becomes lower, while an E-steps correction would usually become higher.
Reference Formulas
- Belt axis starting point: rotation_distance = belt pitch x pulley teeth.
- Leadscrew axis starting point: rotation_distance = screw pitch x number of starts.
- Extruder measured correction: new rotation_distance = current rotation_distance x actual extrusion / commanded extrusion.
- Marlin conversion: rotation_distance = full steps per rotation x microsteps / steps per mm.
Formula
New rotation distance = current rotation distance × actual extrusion / commanded extrusion. Rotation distance from steps/mm = full steps per rotation × microsteps / known steps/mm.
Limits of This Calculator
- The result is an estimate, not a guaranteed shop price or firmware recommendation.
- PrintCostCalc does not fetch live prices, connect to a printer, upload model files, or save quote data.
- Use your slicer, printer documentation, and real test prints to confirm assumptions when accuracy matters.
FAQ
Why is this formula different from E-steps?
Rotation distance is distance per motor rotation, so it is inverse to steps per millimeter.
Does this write to printer.cfg?
No. Copy the result and edit your configuration manually.
Can I convert Marlin E-steps to Klipper rotation_distance?
Yes. Enter full steps per rotation, microsteps, and the known steps/mm value to get the rotation distance reference value.
How do I calibrate extruder rotation_distance with a measured test?
Command a slow 100 mm extrusion, measure the actual filament movement, and enter your current rotation_distance with the commanded and actual lengths. The new rotation_distance equals current rotation_distance times actual divided by commanded extrusion.
What is a good starting rotation_distance for an extruder?
Most direct and Bowden extruders start somewhere between roughly 4 and 8 mm depending on the gear, but you should always confirm with a measured extrusion test rather than trusting a default.