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Sheet gauge

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Type in either box. A comma works as a decimal point (2,5 = 2.5); with both a comma and a point, the comma is read as a thousands separator.

Approximate, for guidance only. These relationships hold for carbon and low-alloy (non-austenitic) steels in the annealed, normalised or quenched-and-tempered condition. They do not apply to austenitic stainless steel, cold-worked material or other metals. A hardness test does not replace a tensile test.

Scale Value

—Rockwell C (HRC)
—Rockwell B (HRB)
—Vickers (HV)
—Brinell (HB)
—Tensile strength, ksi (approx.)
—Tensile strength, MPa (approx.)

Values between table rows are interpolated. A dash means the tables do not cover that scale at this hardness.

Length — common conversions

From	Equals
1 in	25.4 mm
1 ft	0.3048 m
1 m	3.28084 ft
1 0.001 in	0.0254 mm
1 mi	1.60934 km
1 nmi	1.852 km

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is m.

Area — common conversions

From	Equals
1 in²	645.16 mm²
1 ft²	0.092903 m²
1 m²	10.7639 ft²
1 acre	4,046.86 m²
1 ha	2.47105 acre

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is m².

Volume — common conversions

From	Equals
1 m³	35.3147 ft³
1 US gallon	3.78541 L
1 imperial gallon	4.54609 L
1 42 US gal	158.987 L
1 yd³	0.764555 m³

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is m³.

Mass — common conversions

From	Equals
1 t	2,204.62 lb
1 lb	0.453592 kg
1 US	0.907185 t
1 UK	1.01605 t
1 t	1.10231 US
1 t	0.984207 UK

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is kg.

Density — common conversions

From	Equals
7.85 g/cm³	0.283599 lb/in³
7,850 kg/m³	490.059 lb/ft³
1 lb/in³	27.6799 g/cm³
490 lb/ft³	7,849.05 kg/m³

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is kg/m³.

Mass per length — common conversions

From	Equals
1 lb/ft	1.48816 kg/m
1 kg/m	0.671969 lb/ft
1 lb/yd	0.496055 kg/m

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is kg/m.

Mass per area — common conversions

From	Equals
0.9 oz/ft²	274.637 g/m²
275 g/m²	0.901191 oz/ft²
1 lb/ft²	4.88243 kg/m²

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is kg/m².

Force — common conversions

From	Equals
1 kgf	9.80665 N
1 tf	9.80665 kN
1 lbf	4.44822 N
1 1	4.44822 kN
1 US short	8.89644 kN

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is N.

Pressure & stress — common conversions

From	Equals
1 ksi	6.89476 MPa
355 MPa	51.4884 ksi
1 bar	14.5038 psi
1 kgf/mm²	9.80665 MPa
1 kgf/cm²	0.980665 bar
1 atm	101.325 kPa

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is Pa.

Torque — common conversions

From	Equals
1 lbf·ft	1.35582 N·m
1 kgf·m	9.80665 N·m
1 N·m	8.85075 lbf·in
100 N·m	73.7562 lbf·ft

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is N·m.

Energy — common conversions

From	Equals
1 kWh	3.6 MJ
1 BTU	1.05506 kJ
1 kcal	4.1868 kJ
1 kWh	3,412.14 BTU

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is J.

Power — common conversions

From	Equals
1 hp	0.7457 kW
1 kW	1.34102 hp
1 PS	0.735499 kW
1 TR	3.51685 kW
10,000 BTU/h	2.93071 kW

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is W.

Speed — common conversions

From	Equals
100 km/h	62.1371 mph
1 kn	1.852 km/h
1 m/s	196.85 ft/min
60 m/min	196.85 ft/min

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is m/s.

Flow rate — common conversions

From	Equals
1 m³/h	4.40287 gpm
1 L/s	3.6 m³/h
1 cfm	1.69901 m³/h
1,000 bbl/d	6.62447 m³/h

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is m³/s.

Frequency — common conversions

From	Equals
60 rpm	1 Hz
1,500 rpm	25 Hz
50 Hz	3,000 rpm

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is Hz.

Time — common conversions

From	Equals
1 d	24 h
1 week	168 h
1 365 days	365 d
8,760 h	365 d

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is s.

Second moment of area — common conversions

From	Equals
1 in⁴	41.6231 cm⁴
1 cm⁴	10,000 mm⁴
1,000 cm⁴	24.0251 in⁴

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is m⁴.

Section modulus — common conversions

From	Equals
1 in³	16.3871 cm³
100 cm³	6.10237 in³

Factors are exact definitions (NIST SP 811, the SI Brochure); the base unit is m³.

Temperature — common values

°C	°F	K	Note
-40	-40	233.15
0	32	273.15	water freezes
20	68	293.15	room temperature, test temperature
100	212	373.15	water boils
200	392	473.15
550	1,022	823.15	about the tempering range
723	1,333.4	996.15	A1, lower critical temperature of steel
912	1,673.6	1,185.15	A3 of pure iron
1538	2,800.4	1,811.15	iron melts

°F = °C × 9/5 + 32; K = °C + 273.15.

Hardness — approximate equivalents for steel

HRC	HV	HB	Tensile, ksi	Tensile, MPa
68	940	—	—	—
67	900	—	—	—
66	865	—	—	—
65	832	739	—	—
64	800	722	—	—
63	772	706	—	—
62	746	688	—	—
61	720	670	—	—
60	697	654	—	—
59	674	634	351	2,420
58	653	615	338	2,330
57	633	595	325	2,241
56	613	577	313	2,158
55	595	560	301	2,075
54	577	543	292	2,013
53	560	525	283	1,951
52	544	512	273	1,882
51	528	496	264	1,820
50	513	481	255	1,758
49	498	469	246	1,696
48	484	455	238	1,641
47	471	443	229	1,579
46	458	432	221	1,524
45	446	421	215	1,482
44	434	409	208	1,434
43	423	400	201	1,386
42	412	390	194	1,338
41	402	381	188	1,296
40	392	371	182	1,255
39	382	362	177	1,220
38	372	353	171	1,179
37	363	344	166	1,145
36	354	336	161	1,110
35	345	327	156	1,076
34	336	319	152	1,048
33	327	311	149	1,027
32	318	301	146	1,007
31	310	294	141	972
30	302	286	138	951
29	294	279	135	931
28	286	271	131	903
27	279	264	128	883
26	272	258	125	862
25	266	253	123	848
24	260	247	119	820
23	254	243	117	807
22	248	237	115	793
21	243	231	112	772
20	238	226	110	758

Softer steels (Rockwell B range)

HB	HRB	Tensile, ksi	Tensile, MPa
241	100.0	116	800
235	99.0	114	786
229	98.2	111	765
223	97.3	104	717
217	96.4	103	710
212	95.5	100	689
207	94.6	99	683
201	93.8	97	669
197	92.8	94	648
192	91.9	92	634
187	90.7	90	621
183	90.0	89	614
179	89.0	88	607
174	87.8	86	593
170	86.8	84	579
167	86.0	83	572
163	85.0	82	565
156	82.9	80	552
149	80.8	73	503
143	78.7	71	490
137	76.4	67	462
131	74.0	65	448
126	72.0	63	434
121	69.0	60	414
116	67.6	58	400
111	65.7	56	386

Relationships as tabulated for non-austenitic steels in ASTM E140 and ASTM A370; Brinell with a 10 mm tungsten-carbide ball under 3,000 kgf. The commonly cited sour-service limit of 22 HRC is about 248 HV (see the steel calculators).

Wire gauges in millimetres

Gauge	SWG, mm	BWG, mm	AWG, mm
0	8.230	8.636	8.251
1	7.620	7.620	7.348
2	7.010	7.214	6.544
3	6.401	6.579	5.827
4	5.893	6.045	5.189
5	5.385	5.588	4.621
6	4.877	5.156	4.115
7	4.470	4.572	3.665
8	4.064	4.191	3.264
9	3.658	3.759	2.906
10	3.251	3.404	2.588
11	2.946	3.048	2.305
12	2.642	2.769	2.053
13	2.337	2.413	1.828
14	2.032	2.108	1.628
15	1.829	1.829	1.450
16	1.626	1.651	1.291
17	1.422	1.473	1.150
18	1.219	1.245	1.024
19	1.016	1.067	0.912
20	0.914	0.889	0.812
21	0.813	0.813	0.723
22	0.711	0.711	0.644
23	0.610	0.635	0.573
24	0.559	0.559	0.511
25	0.508	0.508	0.455
26	0.457	0.457	0.405
27	0.417	0.406	0.361
28	0.376	0.356	0.321
29	0.345	0.330	0.286
30	0.315	0.305	0.255

SWG and BWG from the wire gauge table in Product info; AWG from its defining series, 0.005 in at gauge 36 and 0.46 in at gauge 0000. Sheet thickness gauges are a different set — see the sheet metal gauge table.

Nail sizes — penny to inches and millimetres

Size	Length, in	Length, mm	Diameter, in	Diameter, mm
2d	1	25.4	0.072	1.83
3d	1.25	31.8	0.080	2.03
4d	1.5	38.1	0.098	2.49
5d	1.75	44.5	0.098	2.49
6d	2	50.8	0.113	2.87
7d	2.25	57.2	0.113	2.87
8d	2.5	63.5	0.131	3.33
9d	2.75	69.9	0.131	3.33
10d	3	76.2	0.148	3.76
12d	3.25	82.6	0.148	3.76
16d	3.5	88.9	0.162	4.11
20d	4	101.6	0.192	4.88
30d	4.5	114.3	0.207	5.26
40d	5	127.0	0.225	5.72
50d	5.5	139.7	0.244	6.20
60d	6	152.4	0.263	6.68

Lengths are the trade definition of the penny sizes; diameters are those of bright common nails (ASTM F1667).

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