Cutting Speed Chart
Recommended surface speed (SFM) by material and tool material, for milling, drilling, and turning alike — the single reference all the speed calculators on this site point back to.
| Material | HSS (SFM) | Carbide (SFM) |
|---|---|---|
| Aluminum (free machining) | 300–600 | 800–2000 |
| Brass (free cutting) | 150–300 | 500–1000 |
| Bronze | 100–200 | 300–600 |
| Mild steel (1018) | 80–110 | 350–550 |
| Alloy steel (4140) | 50–80 | 250–400 |
| Tool steel (hardened) | 20–40 | 100–200 |
| Stainless steel (304) | 40–70 | 200–350 |
| Stainless steel (316) | 30–60 | 150–300 |
| Cast iron (gray) | 60–90 | 300–500 |
| Titanium (Ti-6Al-4V) | 20–30 | 100–180 |
| Plastics (general, e.g. G10/Delrin) | 300–600 | 500–1000 |
Starting points, not a substitute for the tool manufacturer's data sheet — coatings, insert grade, coolant, and rigidity all shift these ranges.
How to use this with the calculators on this site
Pick a material and tool material here, then carry the SFM value straight into the Feed & Speed Calculator, SFM ↔ RPM Calculator, Drill Speed Calculator, or Turning Feed & Speed Calculator to get the RPM and feed rate for your specific tool diameter and setup.
Why these are ranges, not single numbers
The right SFM for a job depends on more than material and tool material alone — insert coating, setup rigidity, coolant (flood, mist, or dry), and how deep a finish you need all push the workable range up or down. Start near the middle of the listed range, move toward the low end if you're seeing excess heat, edge chipping, or chatter, and toward the high end once you've confirmed the setup is rigid and well cooled.
Tool steel and hardened materials need extra caution
Hardened tool steel cuts dramatically slower than its annealed state — if a material has been heat treated, its actual hardness (check a hardness tester or the cert, not an assumption) matters more than the base alloy name for picking a safe starting speed. When in doubt, start at the bottom of the range and work up.