CNC Machining worked example

CNC Program Runtime with in-cut cutting time of 19 min: a worked example

This scenario runs the cnc program runtime calculation on the strong side: in-cut cutting time of 19 min, with every other input held at its documented default. estimating CNC program runtime for scheduling, quoting, machine loading, or program optimization

The inputs for this scenario

  • In-cut cutting time: 19 min (raised for this scenario; the documented default is 7.5)
  • Rapid, approach, and air-cut time: 1.8 min (unchanged)
  • Tool-change, probing, and in-process inspection time: 1.2 min (unchanged)
  • Load, unload, and operator handling allowance: 2 min (unchanged)

Working through the calculation

  • Applying the documented formula (CNC program runtime = cutting time + rapid, approach, and non-cutting time + tool change, probing, and inspection time + load, unload, and operator allowance) to the inputs above produces each figure below.
  • At this operating point the engine returns 24 min for estimated cnc program runtime, the number this scenario is built around.
  • At this operating point the engine returns 19 min for element 1.
  • At this operating point the engine returns 1.8 min for element 2.
  • At this operating point the engine returns 3.2 min for element 3 + 4.

How this compares with the baseline

  • Against the tool's baseline example, where in-cut cutting time sits at 7.5 min and the headline result is 12.5 min, this scenario comes in 92% above the baseline at 24 min.
  • Use it when quoting a new part, building a routing, or sanity-checking estimated cycle time against machine history. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • estimated CNC program runtime: 24 min (headline result)
  • Element 1: 19 min
  • Element 2: 1.8 min
  • Element 3 + 4: 3.2 min

Run it with your numbers

  • Every input above is editable in the live CNC Program Runtime calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.