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Required travel to hit top speed and stop.
If the total move distance is greater than the length of the line you are printing, your printer will never reach the target speed on that segment.
Motion physics calculation based on your inputs.
3D printers don't jump to their target speed instantly. They obey the laws of physics. The print head must accelerate from a standstill, reach the target velocity (if there's enough room), and then decelerate back to zero for the next corner or stop.
The relationship is governed by the kinematic equation:
If you want to print fast, high top speed isn't enough. You need high acceleration. Without it, your printer spends all its time speeding up and slowing down, never reaching the speed you set in the slicer.
High acceleration causes vibrations (ringing/ghosting). For better surface quality, lower your acceleration. This calculator helps you see the trade-off: lower acceleration means you need much longer moves to hit high speeds.
"Input Shaping" (in Klipper/Marlin) allows you to use much higher acceleration values without the ringing artifacts, letting you hit those top speeds even on smaller prints.
| Printer class | Typical print acceleration |
|---|---|
| Stock bed-slinger (e.g. Ender 3), safe | ~500 mm/s² |
| Prusa MK3 / MK4 (stock) | ~1,000–1,250 mm/s² |
| Tuned bed-slinger | ~1,500 mm/s² |
| CoreXY / Voron class (tuned) | 3,000+ mm/s² |
| Klipper input-shaper test sweep | 1,500–7,000 mm/s² |
Start around 500 mm/s² on a stock bed-slinger and raise it until you see ghosting or skipped steps, then back off. A lighter toolhead and CoreXY motion (where the bed doesn't carry the model) tolerate much higher values. Corner speed is handled separately by jerk or junction deviation (Marlin) and square corner velocity (Klipper, default 5 mm/s).
Advertised maxima (some printers cite up to 20,000 mm/s²) are peak marketing figures, not the per-feature accelerations your slicer actually uses.
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