Print time
3D print time calculator
Turn a volume and a slicer profile into hours. Useful when you have a model but no slicer to hand — and honest about the fact that this is an estimate, not a promise.
The model, in one line
hours = volume_mm³ ÷ (layer_height_mm × extrusion_width_mm × speed_mm_per_s) ÷ 3600 × 1.15
In other words: how many cubic millimetres the nozzle can lay down per second, and how many cubic millimetres the part contains. Every factor that makes a real print slower — accelerations, travel, retraction, cooling, small perimeters — is rolled into the flat 15% allowance.
Worked example
120 cm³ at 0.2 mm layers, 0.45 mm wide, 60 mm/s:
0.2 × 0.45 × 60 = 5.4 mm³/s, and
120 000 ÷ 5.4 = 22 222 s = 6.17 h.
With the 15% allowance: 7.10 h, or 5.68–8.52 h at ±20%.
If your slicer says 9 hours for the same part, it is not wrong — the flat allowance is too small for that geometry. That is why the tolerance exists.
When this estimate is worst
- Many small parts on one plate: travel and per-part overhead dominate. Add 10–30% to the estimate.
- Very fine layers on a tall part: per-layer cooling time is not modelled; thin tall prints take longer than the formula says.
- Fast profiles: at 150 mm/s+ the printer rarely reaches the set speed on short segments, so the real average flow is well under the nominal.
- Support-heavy models: support extrusion is not in your model volume. Add it or slice the model.