RPM Calculator

Use this tool to calculate RPM (rotations per minute). All dimensions are in decimal inches.

Turning speeds are optimized for carbide tooling with a feed rate of (0.004/rev.), a depth of cut of 0.040, and a tool life of 180 minutes.

Material	AISI/SAE/ASTM Designation	Surface Feet/Minute
Free machining plain carbon steels (resulfurized)	1212, 1213, 1215	820 - 1045
Free machining plain carbon steels	1108, 1109, 1115, 1117, 1118, 1120, 1126, 1211	950
Free machining plain carbon steels	1132, 1137, 1139, 1140, 1144, 1146, 1151	670 - 800
Free machining plain carbon steels (Leaded)	11L17, 11L18, 12L13, 12L14	800 - 820
Plain carbon steels	1006, 1008, 1009, 1010, 1012, 1015, 1016, 1017, 1018, 1019, 1020, 1021, 1022, 1023, 1024, 1025, 1026, 1513, 1514	800 - 885
Plain carbon steels	1027, 1030, 1033, 1035, 1036, 1037, 1038, 1039, 1040, 1041, 1042, 1043, 1045, 1046, 1048, 1049, 1050, 1052, 1524, 1526, 1527, 1541	670 - 970
Free machining alloy steels (resulfurized):	4140, 4150	430 - 685
Water hardening tool steel	W1, W2, W5	590
Cold work, oil hardening tool steel	O1, O2, O6, O7	590
Cold work, air hardening tool steel	A2, A3, A4, A6, A7, A8, A9, A10	355 - 365
Stainless steels (Austenitic)	201, 202, 301, 302, 304, 304L, 305, 308, 321, 347, 348	570
Cast Iron	ASTM Class 20, 25, 30, 35, 40	410
Brass	C35600, C37700, C36000, C33200, C34200, C35300, C48500, C34000	1170
Bronze	C65500, C22600, C65100, C67500	715
Wrought aluminum	6061-T6, 5000, 6000, and 7000 series.	2820
Cast aluminum	Sand and permanent mold casting alloys	2820

Milling speeds are optimized for high speed steel tooling.

Material	AISI/SAE/ASTM Designation	Surface Feet/Minute
Free machining plain carbon steels (resulfurized)	1212, 1213, 1215	130 - 140
Free machining plain carbon steels	1108, 1109, 1115, 1117, 1118, 1120, 1126, 1211	115 - 130
Free machining plain carbon steels	1132, 1137, 1139, 1140, 1144, 1146, 1151	35 - 70
Free machining plain carbon steels (Leaded)	11L17, 11L18, 12L13, 12L14	110 - 140
Plain carbon steels	1006, 1008, 1009, 1010, 1012, 1015, 1016, 1017, 1018, 1019, 1020, 1021, 1022, 1023, 1024, 1025, 1026, 1513, 1514	65 - 110
Plain carbon steels	1027, 1030, 1033, 1035, 1036, 1037, 1038, 1039, 1040, 1041, 1042, 1043, 1045, 1046, 1048, 1049, 1050, 1052, 1524, 1526, 1527, 1541	25 - 100
Free machining alloy steels (resulfurized)	4140, 4150	35 - 100
Water hardening tool steel	W1, W2, W5	85
Cold work, oil hardening tool steel	O1, O2, O6, O7	50
Cold work, air hardening tool steel	A2, A3, A4, A6, A7, A8, A9, A10	40 - 50
Stainless steels (Austenitic)	201, 202, 301, 302, 304, 304L, 305, 308, 321, 347, 348	70 - 75
Cast Iron	ASTM Class 20, 25, 30, 35, 40	70 - 100
Brass	C33200, C34000, C34200, C35300, C35600, C36000, C37700, C48500	100 - 200
Bronze	C22600, C65100, C65500, C67500	30 - 80
Wrought aluminum	6061-T6, 5000, 6000, and 7000 series.	165
Cast aluminum	Sand and permanent mold casting alloys	165

Drilling and reaming speeds are optimized for high speed steel tooling.

Material	AISI/SAE/ASTM Designation	Drilling Surface Feet/Minute	Reaming Surface Feet/Minute
Free machining plain carbon steels (resulfurized)	1212, 1213, 1215	120 - 125	80
Free machining plain carbon steels	1108, 1109, 1115, 1117, 1118, 1120, 1126, 1211	100 - 120	75 - 80
Free machining plain carbon steels	1132, 1137, 1139, 1140, 1144, 1146, 1151	35 - 70	20 - 45
Free machining plain carbon steels (Leaded)	11L17, 11L18, 12L13, 12L14	90 - 130	60 - 85
Plain carbon steels	1006, 1008, 1009, 1010, 1012, 1015, 1016, 1017, 1018, 1019, 1020, 1021, 1022, 1023, 1024, 1025, 1026, 1513, 1514	60 - 100	40 - 65
Plain carbon steels	1027, 1030, 1033, 1035, 1036, 1037, 1038, 1039, 1040, 1041, 1042, 1043, 1045, 1046, 1048, 1049, 1050, 1052, 1524, 1526, 1527, 1541	25 - 90	15 - 60
Free machining alloy steels (resulfurized)	4140, 4150	30 - 90	15 - 60
Water hardening tool steel	W1, W2, W5	85	55
Cold work, oil hardening tool steel	O1, O2, O6, O7	45	30
Cold work, air hardening tool steel	A2, A3, A4, A6, A7, A8, A9, A10	30 - 50	20 - 35
Stainless steels (Austenitic)	201, 202, 301, 302, 304, 304L, 305, 308, 321, 347, 348	50 - 55	30 - 35
Cast Iron	ASTM Class 20, 25, 30, 35, 40	80 - 100	50 - 65
Brass	C35600, C37700, C36000, C33200, C34200, C35300, C48500, C34000	160 - 175	160 - 175
Bronze	C65500, C22600, C65100, C67500	120 - 140	110 - 120
Wrought aluminum	6061-T6, 5000, 6000, and 7000 series.	350 - 400	350 - 400
Cast aluminum	Sand and permanent mold casting alloys	350 - 400	350 - 400