3D Print Time Estimate Calculator
A quick way to estimate print time is to divide the total length of filament a model consumes by the printer's effective extrusion speed, then apply a factor for the travel and slow-down time that a single average speed cannot capture. This calculator returns the print time in hours and minutes from the filament length, the average print speed in millimetres of filament per second, and a movement-efficiency factor. Use it for a fast estimate before slicing or a sanity check afterwards.
Print time formula
Effective speed = average speed * efficiency factor
Time (seconds) = filament length / effective speed
Time (hours) = time in seconds / 3,600
Length is in millimetres of filament and speed is millimetres of filament extruded per second. The efficiency factor scales the speed down to a realistic average.
Worked example
120,000 mm of filament at 8 mm/s with a 0.7 efficiency factor: effective speed = 8 * 0.7 = 5.6 mm/s. Time = 120,000 / 5.6 = 21,428.57 s = 5.95 hours, about 5 hours 57 minutes.
3D print time: frequently asked questions
How is 3D print time estimated?
If you know the total length of filament a model uses and the printer's average effective print speed in millimetres of filament per second, the print time is simply length divided by speed. A movement-efficiency factor accounts for travel moves, accelerations and non-printing time that slow the real job.
Why include an efficiency factor?
The nozzle is not extruding at full speed for the whole print: it slows for corners, performs travel moves, and pauses for retractions and layer changes. An efficiency factor below 1 (for example 0.7) reduces the theoretical speed to a realistic average. Adjust it to match your printer and model.
Is this as accurate as my slicer?
No. A slicer simulates every move and is more accurate. This calculator gives a quick estimate before slicing, or a sanity check afterwards, using a single average speed rather than a full motion simulation.
Official sources
- U.S. National Institute of Standards and Technology: Additive Manufacturing.
- The time estimate follows from the definition of speed as distance divided by time.
Reviewed by the CalculatorHub team, edited by James Graham, 19 June 2026. See our methodology.