3D Printing Calculators

FDM core & costs

Print Time Estimator

Slicer time assumes the printer actually reaches the profile speed. Split the job into typical move lengths, accelerate from jerk as a junction velocity, and add print plus travel. Short segments never see the headline mm/s.

Inputs

Units
mm

Extruding moves. Slicers sometimes report this as filament travel for print moves.

mm/s
mm
mm/s
mm/s²

Firmware accel. Not converted — millimetres per second squared in both unit systems.

mm/s

Instantaneous corner speed (classic jerk), not S-curve jerk in mm/s³.

mm

Typical segment between junctions. Infill and small letters are shorter than this.

Results

Total time
2,192.8s
Total time
0.609h
Print moves
2,066.7s
Travel moves
126.1s

Recommended gear

Calculation method

Each motion class (print, travel) is split into n = max(1, round(path / average move)) equal segments of length d. Junction velocity v0 is min(jerk, vmax). Distance to reach vmax is (vmax² − v0²) / (2a). If two of those ramps fit in d, time is a trapezoid: 2(vmax − v0)/a plus cruise. Otherwise a symmetric triangle: v_peak = √(v0² + a d) and t = 2(v_peak − v0)/a. Total seconds is n times each class. Acceleration and jerk stay in millimetres; path and speed toggle with the unit switch. Invalid when accel or a speed is not positive.

Exact formula

n = max(1, round(path / average_move)), d = path / n. v0 = min(jerk, vmax). d_accel = (vmax² − v0²) / (2a). Trapezoid if 2 d_accel ≤ d, else triangle with v_peak = √(v0² + a d). Limits: Ignores retraction, layer-change waits, input-shaper derate and first-layer babysitting. Not a G-code simulator.

Average move is the fudge

A vase is one long spiral (raise average move). A miniature is thousands of 2 mm hops (lower it). Recalculate when the geometry class changes.

Travel still costs time

Sparse infill with lots of hopping can make travel seconds a real share of the job even at 150 mm/s.

Frequently asked questions

Is this Marlin jerk or Klipper square cornering?

It is the old instantaneous junction speed idea. Treat Klipper square_corner_velocity as jerk here. It is not the S-curve jerk in mm/s³.

Why is slicer time different?

Slicers see every segment, retraction, and look-ahead. This uses one average move length. Tiny letters will be slower than the estimate.

Where do I get path length?

Some slicers show travel and extrusion distance. If you only have hours from the slicer, this tool is for what-if speed and accel changes.

Does input shaping change the formula?

Shaping can cap accel. Put the shaped accel in the acceleration field rather than the unshaped wish.

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