Feeds & SpeedsChip load tuningSave tools
CNC Feed Rate Calculator
Optimize spindle speed and feed rate for smooth, efficient CNC machining. Use chip load as your compass so you cut chips, not dust.
Quick-start tuning
- Dust = too slow (raise feed or lower RPM). Chips = happier cutter.
- Burning = heat buildup (improve evacuation, adjust chip load).
- Chatter = rigidity problem (reduce depth/width, adjust RPM).
Best practice: start conservative, run a test pass, then iterate one variable at a time.
CNC Feed Rate Converter
Convert between feed rate, spindle speed, flutes, and chip load for CNC milling or routing operations.
Formula
Feed Rate
Feed Rate = RPM × Flutes × Chip LoadIf your spindle has a max RPM, chip load becomes your lever for balancing heat and finish.
How to use
- Select tool diameter and flute count.
- Pick a starting chip load (manufacturer data when possible).
- Adjust RPM and feed to produce chips (not dust) without chatter.
- Verify with a test pass and watch heat + edge finish.
Pro tips
- • Increase feed or lower RPM if you’re making dust instead of chips.
- • Downcut: best top finish. Upcut: best chip evacuation. Compression: good both sides.
- • Sharp tools win. Worn tools need less chip load and create more heat.
- • Dust collection matters: recutting chips increases heat and dulls bits.
FAQs
What if it burns?
Burning usually means heat buildup. Increase feed, reduce RPM, improve chip evacuation, or reduce depth per pass. Make one change at a time.
Do I need dust collection?
Yes. Poor extraction recuts chips, increases heat, worsens finish, and accelerates tool wear.