CNC calculators
Three calculators, all free, all running in your browser - nothing you type is sent anywhere. Two of them work out how to cut, and one works out what to charge. Every figure they produce is traceable: the chip-load reference table is published in full on the methodology page (currently 2026.07-1), and each result shows the arithmetic that produced it rather than presenting a number to be trusted.
Which calculator you want
Feed & speed calculator
Turns your material, cutter, diameter, flutes, RPM and depth of cut into a feed rate, a plunge rate and the chip load that results.
Start here. This is the one you open before a job you have not run before, and the one that tells you whether the numbers you were about to type are inside the published range for that material.
Chip load calculator
Works in both directions: a target chip load out to a feed rate, or an existing feed rate back to the chip load it is actually producing.
Reach for this when you already have a feed rate - inherited from a forum post, a preset or a previous job - and want to know what it is doing to the cutter before you run it again.
Project cost & pricing calculator
Material, machine time, tooling wear, power and labour worked into a cost per part and a suggested price, with one-off setup kept separate from per-part cost.
Use it when someone asks what you charge. It is the only one of the three that is about the business rather than the cut.
Straight to your material
Each material has its own page with the feed & speed calculator pre-filled to that material's chip-load range, so you can skip the setup entirely.
What these numbers are, and are not
Every figure here is calculated from published tooling-manufacturer reference data, not measured on a machine. They are a defensible starting point, and they are frequently better than the number a machine ships with - but they cannot know your machine's rigidity, the state of your cutter, how well your work is held down, or whether your spindle holds its commanded RPM under load. Prove a new setting on scrap before you commit a finished piece to it.
If a cut is already going wrong, the calculator is usually the second thing to check rather than the first. The troubleshooting guides start from the symptom, and the how-to-cut guides cover the things a feed rate cannot fix - which bit, how to hold the work, and how to clear chips.