Thread & Gage Reference Charts

English Thread Plug GagesStandard pitch diameter chart — internal threads (Class 2B / 3B)

Nominal Size	GO Basic all classes	NO GO Class 2B	NO GO Class 3B	X Tol. GO +, NO GO −	X Lead Tol.	X Half-Angle Tol.
#0-80 UNF	0.0519	0.0542	0.0536	0.0002	0.0002	0°30'
#1-64 UNC	0.0629	0.0655	0.0648	0.0002	0.0002	0°30'
#1-72 UNF	0.0640	0.0665	0.0659	0.0002	0.0002	0°30'
#2-56 UNC	0.0744	0.0772	0.0765	0.0002	0.0002	0°30'
#2-64 UNF	0.0759	0.0786	0.0779	0.0002	0.0002	0°30'
#3-48 UNC	0.0855	0.0885	0.0877	0.0002	0.0002	0°30'
#3-56 UNF	0.0874	0.0902	0.0895	0.0002	0.0002	0°30'
#4-40 UNC	0.0958	0.0991	0.0982	0.0002	0.0002	0°20'
#4-48 UNF	0.0985	0.1016	0.1008	0.0002	0.0002	0°30'
#5-40 UNC	0.1088	0.1121	0.1113	0.0002	0.0002	0°20'
#5-44 UNF	0.1102	0.1134	0.1126	0.0002	0.0002	0°20'
#6-32 UNC	0.1177	0.1214	0.1204	0.0003	0.0003	0°15'
#6-40 UNF	0.1218	0.1252	0.1243	0.0002	0.0002	0°20'
#8-32 UNC	0.1437	0.1475	0.1465	0.0003	0.0003	0°15'
#8-36 UNF	0.1460	0.1496	0.1487	0.0002	0.0002	0°20'
#10-24 UNC	0.1629	0.1672	0.1661	0.0003	0.0003	0°15'
#10-32 UNF	0.1697	0.1736	0.1726	0.0003	0.0003	0°15'
#12-24 UNC	0.1889	0.1933	0.1922	0.0003	0.0003	0°15'
#12-28 UNF	0.1928	0.1970	0.1959	0.0003	0.0003	0°15'
#12-32 UNEF	0.1957	0.1998	0.1988	0.0003	0.0003	0°15'
1/4-20 UNC	0.2175	0.2224	0.2211	0.0003	0.0003	0°15'
1/4-28 UNF	0.2268	0.2311	0.2300	0.0003	0.0003	0°15'
1/4-32 UNEF	0.2297	0.2339	0.2328	0.0003	0.0003	0°15'
5/16-18 UNC	0.2764	0.2817	0.2803	0.0003	0.0003	0°10'
5/16-24 UNF	0.2854	0.2902	0.2890	0.0003	0.0003	0°15'
5/16-32 UNEF	0.2922	0.2964	0.2953	0.0003	0.0003	0°15'
3/8-16 UNC	0.3344	0.3401	0.3387	0.0003	0.0003	0°10'
3/8-24 UNF	0.3479	0.3528	0.3516	0.0003	0.0003	0°15'
3/8-32 UNEF	0.3547	0.3591	0.3580	0.0003	0.0003	0°15'
7/16-14 UNC	0.3911	0.3972	0.3957	0.0003	0.0003	0°10'
7/16-20 UNF	0.4050	0.4104	0.4091	0.0003	0.0003	0°15'
7/16-28 UNEF	0.4143	0.4189	0.4178	0.0003	0.0003	0°15'
1/2-13 UNC	0.4500	0.4565	0.4548	0.0003	0.0003	0°10'
1/2-20 UNF	0.4675	0.4731	0.4717	0.0003	0.0003	0°15'
1/2-28 UNEF	0.4768	0.4816	0.4804	0.0003	0.0003	0°15'
9/16-12 UNC	0.5084	0.5152	0.5135	0.0003	0.0003	0°10'
9/16-18 UNF	0.5264	0.5323	0.5308	0.0003	0.0003	0°10'
9/16-24 UNEF	0.5354	0.5405	0.5392	0.0003	0.0003	0°15'
5/8-11 UNC	0.5660	0.5732	0.5714	0.0003	0.0003	0°15'
5/8-18 UNF	0.5889	0.5949	0.5934	0.0003	0.0003	0°10'
5/8-24 UNEF	0.5979	0.6031	0.6018	0.0003	0.0003	0°10'
11/16-24 UNEF	0.6604	0.6656	0.6643	0.0003	0.0003	0°15'
3/4-10 UNC	0.6850	0.6927	0.6907	0.0003	0.0003	0°10'
3/4-16 UNF	0.7094	0.7159	0.7143	0.0003	0.0003	0°10'
3/4-20 UNEF	0.7175	0.7232	0.7218	0.0003	0.0003	0°15'
13/16-20 UNEF	0.7800	0.7857	0.7843	0.0003	0.0003	0°15'
7/8-9 UNC	0.8028	0.8110	0.8089	0.0003	0.0003	0°10'
7/8-14 UNF	0.8286	0.8356	0.8339	0.0003	0.0003	0°10'
7/8-20 UNEF	0.8425	0.8482	0.8468	0.0003	0.0003	0°15'
15/16-20 UNEF	0.9050	0.9109	0.9094	0.0003	0.0003	0°15'
1"-8 UNC	0.9188	0.9276	0.9254	0.0004	0.0004	0°05'
1"-12 UNF	0.9459	0.9535	0.9516	0.0003	0.0003	0°10'
1"-14 UNS	0.9536	0.9609	0.9590	0.0003	0.0003	0°10'
1"-20 UNEF	0.9675	0.9734	0.9719	0.0003	0.0003	0°15'
1 1/16-12 UN	1.0084	1.0158	1.0139	0.0003	0.0003	0°10'
1 1/16-18 UNEF	1.0264	1.0326	1.0310	0.0003	0.0003	0°10'
1 1/8-7 UNC	1.0322	1.0416	1.0393	0.0004	0.0004	0°05'
1 1/8-12 UNF	1.0709	1.0787	1.0768	0.0003	0.0003	0°10'
1 1/8-18 UNEF	1.0889	1.0951	1.0935	0.0003	0.0003	0°10'
1 3/16-12 UN	1.1334	1.1409	1.1390	0.0003	0.0003	0°10'
1 3/16-18 UNEF	1.1514	1.1577	1.1561	0.0003	0.0003	0°10'
1 1/4-7 UNC	1.1572	1.1668	1.1644	0.0004	0.0004	0°05'
1 1/4-12 UNF	1.1959	1.2039	1.2019	0.0003	0.0003	0°10'
1 1/4-18 UNEF	1.2139	1.2202	1.2186	0.0003	0.0003	0°10'
1 5/16-12 UN	1.2584	1.2659	1.2640	0.0003	0.0003	0°10'
1 5/16-18 UNEF	1.2764	1.2827	1.2811	0.0003	0.0003	0°10'
1 3/8-6 UNC	1.2667	1.2771	1.2745	0.0004	0.0004	0°05'
1 3/8-12 UNF	1.3209	1.3291	1.3270	0.0003	0.0003	0°10'
1 3/8-18 UNEF	1.3389	1.3452	1.3436	0.0003	0.0003	0°10'
1 7/16-12 UN	1.3834	1.3910	1.3891	0.0003	0.0003	0°10'
1 7/16-18 UNEF	1.4014	1.4079	1.4062	0.0003	0.0003	0°10'
1 1/2-6 UNC	1.3917	1.4022	1.3996	0.0004	0.0004	0°05'
1 1/2-12 UNF	1.4459	1.4542	1.4522	0.0003	0.0003	0°10'
1 1/2-18 UNEF	1.4639	1.4704	1.4687	0.0003	0.0003	0°10'

No rows match that search.

Verified against published pitch diameter charts and confirmed computationally (basic PD = D − 0.649519 × P) on all 74 rows.

English Thread Ring & Setting Plug GagesStandard pitch diameter chart — external threads (Class 2A / 3A)

Nominal Size	Class 2A		Class 3A		X Tol. GO −, NO GO +
Nominal Size	GO	NO GO	GO	NO GO	X Tol. GO −, NO GO +
#0-80 UNF	0.0514	0.0496	0.0519	0.0506	0.0002
#1-64 UNC	0.0623	0.0603	0.0629	0.0614	0.0002
#1-72 UNF	0.0634	0.0615	0.0640	0.0626	0.0002
#2-56 UNC	0.0738	0.0717	0.0744	0.0728	0.0002
#2-64 UNF	0.0753	0.0733	0.0759	0.0744	0.0002
#3-48 UNC	0.0848	0.0825	0.0855	0.0838	0.0002
#3-56 UNF	0.0867	0.0845	0.0874	0.0858	0.0002
#4-40 UNC	0.0950	0.0925	0.0958	0.0939	0.0002
#4-48 UNF	0.0978	0.0954	0.0985	0.0967	0.0002
#5-40 UNC	0.1080	0.1054	0.1088	0.1069	0.0002
#5-44 UNF	0.1095	0.1070	0.1102	0.1083	0.0002
#6-32 UNC	0.1169	0.1141	0.1177	0.1156	0.0003
#6-40 UNF	0.1210	0.1184	0.1218	0.1198	0.0002
#8-32 UNC	0.1428	0.1399	0.1437	0.1415	0.0003
#8-36 UNF	0.1452	0.1424	0.1460	0.1439	0.0002
#10-24 UNC	0.1619	0.1586	0.1629	0.1604	0.0003
#10-32 UNF	0.1688	0.1658	0.1697	0.1674	0.0003
#12-24 UNC	0.1879	0.1845	0.1889	0.1863	0.0003
#12-28 UNF	0.1918	0.1886	0.1928	0.1904	0.0003
#12-32 UNEF	0.1948	0.1917	0.1957	0.1933	0.0003
1/4-20 UNC	0.2164	0.2127	0.2175	0.2147	0.0003
1/4-28 UNF	0.2258	0.2225	0.2268	0.2243	0.0003
1/4-32 UNEF	0.2287	0.2255	0.2297	0.2273	0.0003
5/16-18 UNC	0.2752	0.2712	0.2764	0.2734	0.0003
5/16-24 UNF	0.2843	0.2806	0.2854	0.2827	0.0003
5/16-32 UNEF	0.2912	0.2880	0.2922	0.2898	0.0003
3/8-16 UNC	0.3331	0.3287	0.3344	0.3311	0.0003
3/8-24 UNF	0.3468	0.3430	0.3479	0.3450	0.0003
3/8-32 UNEF	0.3537	0.3503	0.3547	0.3522	0.0003
7/16-14 UNC	0.3897	0.3850	0.3911	0.3876	0.0003
7/16-20 UNF	0.4037	0.3995	0.4050	0.4019	0.0003
7/16-28 UNEF	0.4132	0.4096	0.4143	0.4116	0.0003
1/2-13 UNC	0.4485	0.4435	0.4500	0.4463	0.0003
1/2-20 UNF	0.4662	0.4619	0.4675	0.4643	0.0003
1/2-28 UNEF	0.4757	0.4720	0.4768	0.4740	0.0003
9/16-12 UNC	0.5068	0.5016	0.5084	0.5045	0.0003
9/16-18 UNF	0.5250	0.5205	0.5264	0.5230	0.0003
9/16-24 UNEF	0.5342	0.5303	0.5354	0.5325	0.0003
5/8-11 UNC	0.5644	0.5589	0.5660	0.5619	0.0003
5/8-18 UNF	0.5875	0.5828	0.5889	0.5854	0.0002
5/8-24 UNEF	0.5967	0.5927	0.5979	0.5949	0.0003
11/16-24 UNEF	0.6592	0.6552	0.6604	0.6574	0.0003
3/4-10 UNC	0.6832	0.6773	0.6850	0.6806	0.0003
3/4-16 UNF	0.7079	0.7029	0.7094	0.7056	0.0003
3/4-20 UNEF	0.7162	0.7118	0.7175	0.7142	0.0003
13/16-20 UNEF	0.7787	0.7743	0.7800	0.7767	0.0003
7/8-9 UNC	0.8009	0.7946	0.8028	0.7981	0.0003
7/8-14 UNF	0.8270	0.8216	0.8286	0.8245	0.0003
7/8-20 UNEF	0.8412	0.8368	0.8425	0.8392	0.0003
15/16-20 UNEF	0.9036	0.8991	0.9050	0.9016	0.0003
1"-8 UNC	0.9168	0.9100	0.9188	0.9137	0.0004
1"-12 UNF	0.9441	0.9382	0.9459	0.9415	0.0003
1"-14 UNS	0.9519	0.9463	0.9536	0.9494	0.0003
1"-20 UNEF	0.9661	0.9616	0.9675	0.9641	0.0003
1 1/16-12 UN	1.0067	1.0010	1.0084	1.0042	0.0003
1 1/16-18 UNEF	1.0250	1.0203	1.0264	1.0228	0.0003
1 1/8-7 UNC	1.0300	1.0228	1.0322	1.0268	0.0004
1 1/8-12 UNF	1.0691	1.0631	1.0709	1.0664	0.0003
1 1/8-18 UNEF	1.0875	1.0828	1.0889	1.0853	0.0003
1 3/16-12 UN	1.1317	1.1259	1.1334	1.1291	0.0003
1 3/16-18 UNEF	1.1499	1.1450	1.1514	1.1478	0.0003
1 1/4-7 UNC	1.1550	1.1476	1.1572	1.1517	0.0004
1 1/4-12 UNF	1.1941	1.1879	1.1959	1.1913	0.0003
1 1/4-18 UNEF	1.2124	1.2075	1.2139	1.2103	0.0003
1 5/16-12 UN	1.2567	1.2509	1.2584	1.2541	0.0003
1 5/16-18 UNEF	1.2749	1.2700	1.2764	1.2728	0.0003
1 3/8-6 UNC	1.2643	1.2563	1.2667	1.2607	0.0004
1 3/8-12 UNF	1.3190	1.3127	1.3209	1.3162	0.0003
1 3/8-18 UNEF	1.3374	1.3325	1.3389	1.3353	0.0003
1 7/16-12 UN	1.3816	1.3757	1.3834	1.3790	0.0003
1 7/16-18 UNEF	1.3999	1.3949	1.4014	1.3975	0.0003
1 1/2-6 UNC	1.3893	1.3812	1.3917	1.3856	0.0004
1 1/2-12 UNF	1.4440	1.4376	1.4459	1.4411	0.0003
1 1/2-18 UNEF	1.4624	1.4574	1.4639	1.4602	0.0003

No rows match that search.

Metric Work Plugs, Thread Rings & Setting PlugsStandard pitch diameter chart — 6g external / 6H internal

Size & Pitch	6g GO Ring		6g NO GO Ring		6H GO Plug		6H NO GO Plug
Size & Pitch	mm	in	mm	in	mm	in	mm	in
M1.6x0.35	1.354	.05331	1.291	.05083	1.373	.05406	1.458	.05740
M2x0.4	1.721	.06776	1.654	.06512	1.740	.06850	1.830	.07205
M2.5x0.45	2.188	.08614	2.117	.08335	2.208	.08693	2.303	.09067
M3x0.5	2.655	.10453	2.580	.10157	2.675	.10531	2.775	.10925
M3.5x0.6	3.089	.12161	3.004	.11827	3.110	.12244	3.222	.12685
M4x0.7	3.523	.13870	3.433	.13516	3.545	.13957	3.663	.14421
M5x0.8	4.456	.17543	4.361	.17169	4.480	.17638	4.605	.18130
M6x1.0	5.324	.20961	5.212	.20520	5.350	.21063	5.500	.21654
M8x1.25	7.160	.28189	7.042	.27724	7.188	.28299	7.348	.28929
M8x1.0	7.324	.28835	7.212	.28394	7.350	.28937	7.500	.29528
M10x1.5	8.994	.35409	8.862	.34890	9.026	.35535	9.206	.36244
M10x1.25	9.160	.36063	9.042	.35598	9.188	.36173	9.348	.36803
M10x1.0	9.324	.36709	9.212	.36268	9.350	.36811	9.500	.37402
M10x0.75	9.491	.37366	9.391	.36972	9.513	.37453	9.645	.37972
M12x1.75	10.829	.42634	10.679	.42043	10.863	.42768	11.063	.43555
M12x1.5	10.994	.43283	10.854	.42732	11.026	.43409	11.216	.44157
M12x1.25	11.160	.43937	11.028	.43417	11.188	.44047	11.368	.44756
M12x1.0	11.324	.44583	11.206	.44118	11.350	.44685	11.510	.45315
M14x2.0	12.663	.49854	12.503	.49224	12.701	.50004	12.913	.50839
M14x1.5	12.994	.51157	12.854	.50606	13.026	.51283	13.216	.52031
M15x1.0	14.324	.56394	14.206	.55929	14.350	.56496	14.510	.57126
M16x2.0	14.663	.57728	14.503	.57098	14.701	.57878	14.913	.58713
M16x1.5	14.994	.59031	14.854	.58480	15.026	.59157	15.216	.59906
M17x1.0	16.324	.64268	16.206	.63803	16.350	.64370	16.510	.65000
M18x1.5	16.994	.66906	16.854	.66354	17.026	.67031	17.216	.67780
M20x2.5	18.334	.72181	18.164	.71512	18.376	.72346	18.600	.73228
M20x1.5	18.994	.74780	18.854	.74228	19.026	.74906	19.216	.75654
M20x1.0	19.324	.76079	19.206	.75614	19.350	.76181	19.510	.76811
M22x2.5	20.334	.80055	20.164	.79386	20.376	.80220	20.600	.81102
M22x1.5	20.994	.82654	20.854	.82102	21.026	.82780	21.216	.83528
M24x3.0	22.003	.86626	21.803	.85839	22.051	.86815	22.316	.87858
M24x2.0	22.663	.89224	22.493	.88555	22.701	.89374	22.925	.90256
M25x1.5	23.994	.94465	23.844	.93874	24.026	.94591	24.226	.95378
M27x3.0	25.003	.98437	24.803	.97650	25.051	.98626	25.316	.99669
M27x2.0	25.663	1.01035	25.493	1.00366	25.701	1.01185	25.925	1.02067
M30x3.5	27.674	1.08953	27.462	1.08118	27.727	1.09161	28.007	1.10264
M30x2.0	28.663	1.12846	28.493	1.12177	28.701	1.12996	28.925	1.13878
M30x1.5	28.994	1.14150	28.844	1.13559	29.026	1.14276	29.226	1.15063
M33x2.0	31.663	1.24657	31.493	1.23988	31.701	1.24807	31.925	1.25689
M35x1.5	33.994	1.33835	33.844	1.33244	34.026	1.33961	34.226	1.34748
M36x4.0	33.342	1.31268	33.118	1.30386	33.402	1.31504	33.702	1.32685
M36x2.0	34.663	1.36469	34.493	1.35799	34.701	1.36618	34.925	1.37500
M39x2.0	37.663	1.48280	37.493	1.47610	37.701	1.48429	37.925	1.49311

No rows match that search.

Straight Pipe Thread Pitch DiametersNPSM, NPSC, and NPSL

Nominal Size	NPSM Internal 2B		NPSM External 2A		NPSC Internal		NPSL Internal		NPSL External
Nominal Size	GO	NO GO	GO	NO GO	GO	NO GO	GO	NO GO	GO	NO GO
1/8-27	.3736	.3783	.3725	.3689	.3701	.3771	.3863	.3898	.3840	.3805
1/4-18	.4916	.4974	.4903	.4859	.4864	.4968	.5073	.5125	.5038	.4986
3/8-18	.6270	.6329	.6256	.6211	.6218	.6322	.6444	.6496	.6409	.6357
1/2-14	.7784	.7851	.7769	.7718	.7717	.7851	.8008	.8075	.7963	.7896
3/4-14	.9889	.9958	.9873	.9820	.9822	.9956	1.0112	1.0179	1.0067	1.0000
1-11 1/2	1.2386	1.2462	1.2369	1.2311	1.2305	1.2468	1.2658	1.2739	1.2604	1.2523
1 1/4-11 1/2	1.5834	1.5912	1.5816	1.5756	1.5752	1.5915	1.6106	1.6187	1.6051	1.5970
1 1/2-11 1/2	1.8223	1.8302	1.8205	1.8144	1.8142	1.8305	1.8495	1.8576	1.8441	1.8360
2-11 1/2	2.2963	2.3044	2.2944	2.2882	2.2881	2.3044	2.3234	2.3315	2.3180	2.3099
2 1/2-8	2.7622	2.7720	2.7600	2.7526	2.7504	2.7739	2.8012	2.8129	2.7934	2.7817
3-8	3.3885	3.3984	3.3862	3.3786	3.3768	3.4002	3.4276	3.4393	3.4198	3.4081

No rows match that search.

Column grouping verified against published NPSM / NPSC / NPSL charts.

Thread Form ReferenceBasic form constants by thread series (P = pitch)

Thread Form	Included Angle	Theoretical Depth	Actual Depth	Root Radius
Unified / American (UNC, UNF)	60°	H = 0.86603 × P	0.54127 × P	r = 0.14434 × P
ISO Metric	60°	H = 0.86603 × P	0.54127 × P	r = 0.125 × P
British Standard Whitworth (BSW)	55°	H = 0.960491 × P	0.640327 × P	R = 0.137329 × P
British Association (BA)	47.5°	H = 1.13634 × P	0.60000 × P	R = 0.18083 × P

No rows match that search.

The original sheet used scanned diagrams from published standards. Those should be redrawn as original artwork rather than reproduced.

Jacobs Taper DimensionsInches

Taper No.	A	D	B
0	0.2500	0.2284	0.4375
1	0.3840	0.3334	0.6563
2	0.5590	0.4876	0.8750
2A	0.5488	0.4876	0.7500
3	0.8110	0.7461	1.2100
4	1.1240	1.0372	1.6563
5	1.4130	1.3161	1.8750
6	0.6760	0.6241	1.0000
33	0.6240	0.5605	1.0000

No rows match that search.

Morse Taper DimensionsInches

Taper No.	A	D	K	L	B
0	0.3561	0.2520	1.9375	0.5625	2.3438
1	0.4750	0.3690	2.0625	0.7500	2.5625
2	0.7000	0.5720	2.5000	0.8750	3.1250
3	0.9380	0.7780	3.0625	1.1875	3.8750
4	1.2310	1.0200	3.8750	1.2500	4.8750
5	1.7480	1.4750	4.9375	1.5000	6.1250
6	2.4940	2.1160	7.0000	1.7500	8.5625
7	3.2700	2.7500	9.5000	2.6250	11.6250

No rows match that search.

Decimal & Metric Equivalents of FractionsFractions of an inch

Fraction	Decimal (in)	Millimeters
1/64	.0156	0.396
1/32	.0313	0.795
3/64	.0469	1.191
1/20	.0500	1.270
1/16	.0625	1.588
1/13	.0769	1.953
5/64	.0781	1.984
1/12	.0833	2.116
1/11	.0909	2.309
3/32	.0938	2.383
1/10	.1000	2.540
7/64	.1094	2.779
1/9	.1111	2.822
1/8	.1250	3.175
9/64	.1406	3.571
1/7	.1429	3.630
5/32	.1563	3.967
1/6	.1667	4.234
11/64	.1719	4.366
3/16	.1875	4.763
1/5	.2000	5.080
13/64	.2031	5.159
7/32	.2188	5.558
15/64	.2344	5.954
1/4	.2500	6.350
17/64	.2656	6.746
9/32	.2813	7.145
19/64	.2969	7.541
5/16	.3125	7.938
21/64	.3281	8.334
1/3	.3333	8.466
11/32	.3438	8.733
23/64	.3594	9.129
3/8	.3750	9.525
25/64	.3906	9.921
13/32	.4063	10.320
27/64	.4219	10.716
7/16	.4375	11.113
29/64	.4531	11.509
15/32	.4688	11.908
31/64	.4844	12.304
1/2	.5000	12.700
33/64	.5156	13.096
17/32	.5313	13.495
35/64	.5469	13.891
9/16	.5625	14.288
37/64	.5781	14.684
19/32	.5938	15.083
39/64	.6094	15.479
5/8	.6250	15.875
41/64	.6406	16.271
21/32	.6563	16.670
43/64	.6719	17.066
11/16	.6875	17.463
45/64	.7031	17.859
23/32	.7188	18.258
47/64	.7344	18.654
3/4	.7500	19.050
49/64	.7656	19.446
25/32	.7813	19.845
51/64	.7969	20.241
13/16	.8125	20.638
53/64	.8281	21.034
27/32	.8438	21.433
55/64	.8594	21.829
7/8	.8750	22.225
57/64	.8906	22.621
29/32	.9063	23.020
59/64	.9219	23.416
15/16	.9375	23.813
61/64	.9531	24.209
31/32	.9688	24.608
63/64	.9844	25.004
1	1.0000	25.400

No rows match that search.

Mill & Lathe Formulas and ConversionsSpeeds, feeds, threads, geometry, and unit conversion

Group	To Find	Formula
Speeds & Feeds	Surface Feet per Minute	SFM = RPM × D × 0.2618
Speeds & Feeds	Revolutions per Minute	RPM = (SFM × 3.8197) ÷ D
Speeds & Feeds	Surface Meters per Minute	SMPM = SFM × 0.3048
Speeds & Feeds	Milling Feedrate	IPM = FPT × T × RPM
Speeds & Feeds	Feed per Tooth (mill)	FPT = IPM ÷ (T × RPM)
Speeds & Feeds	Feed per Revolution	FPR = IPM ÷ RPM
Speeds & Feeds	Inches per Minute (lathe)	IPM = IPR × RPM
Speeds & Feeds	Metal Removal Rate	MRR = W × d × F
Threads	Lathe Threading Feedrate	IPR = 1 ÷ TPI
Threads	Mill Tapping Feedrate	IPM = (1 ÷ TPI) × RPM
Threads	Mill Tapping Feedrate (metric)	IPM = RPM × pitch (mm) ÷ 25.4
Threads	Tap Drill Size (inch)	Drill ≈ Major Dia. − (% thread × 0.01299 × 2 ÷ TPI)
Threads	Percentage of Full Thread	% = (Major Dia. − Drill Dia.) × TPI ÷ 0.01299
Geometry	Circumference of a Circle	C = D × 3.1416
Geometry	Area of a Circle	A = R² × 3.1416
Geometry	Diameter from Circumference	D = C × 0.31831
Geometry	Radius from Circumference	R = C × 0.159155
Conversions	Inch to Millimeter	mm = inch × 25.4
Conversions	Millimeter to Inch	inch = mm × 0.03937
Conversions	Foot to Millimeter	mm = foot × 304.8
Conversions	Meter to Inch	inch = meter × 39.37
Conversions	Mile to Kilometer	km = mile × 1.609
Conversions	Kilometer to Mile	mile = km × 0.6214
Conversions	Fahrenheit to Celsius	°C = (°F − 32) × 5 ÷ 9
Conversions	Celsius to Fahrenheit	°F = (°C × 9 ÷ 5) + 32

No rows match that search.

Several formulas on the source sheet were transcribed incorrectly and have been restated in standard form. Verify against your own practice before use.