CNC Feed Rate & Chip Load Calculator
Solve feed rate, chip load or spindle RPM from the other two and the actual cutter flute count.
Set up your calculation
An illustrative example is loaded. Replace its values with your measurements, costs or documented settings.
Tooling help: Upcut vs downcut · Collet & stickout
Calculation
Your result
- Feed rate
- 3,600 mm/min
- Feed in alternate unit
- 141.732 in/min
- Chip load
- 0.1 mm/tooth
- Spindle speed
- 18,000 RPM
The quote handoff carries your inputs and assumptions. Only an explicit base cost is suggested as a quote cost; prices, rates and measurements remain planning notes.
How it works
Feed = RPM × flutes × chip load. Chip load = feed ÷ (RPM × flutes). RPM = feed ÷ (flutes × chip load).
- Use manufacturer chip-load guidance for the exact tool, material and depth of cut. The result is arithmetic, not a machine-approved cutting setting.
Check the feed-rate arithmetic
| Input or step | Example value |
|---|---|
| Spindle speed | 18,000 RPM |
| Cutting flutes | 2 |
| Illustrative chip load | 0.1 mm per tooth |
| Calculated feed | 18,000 × 2 × 0.1 = 3,600 mm/min |
| Equivalent imperial feed | 141.73 in/min |
This is a math example, not a recommended cutting setting. Use documented tool and material guidance and check your machine, engagement, and workholding.
Common questions
Does the calculated feed prove a setup is suitable?
No. It relates RPM, flute count, and chip load. Tool geometry, material, depth, engagement, machine limits, and workholding still need to be checked.
Can I mix inch chip load with millimeter feed?
No. Keep length units consistent. Select the unit that matches your chip-load input; the result also shows the alternate feed unit.
Choose the tool and check the setup
Understand the cutting profile, material reference and equipment limits before applying the result.
Learn the method in the Academy
Follow the matching lesson or workshop reference before applying the result.
Use this in your project
Continue with the next measurement or cost, then keep the assumptions with your quote.
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