Steel Hardness Conversion to Rockwell C Scale

2026/05/07

Rockwell C hardness (HRC)	Vickers Hardness (HV)	Brinell Hardness (HB) 10 mm ball, 3000 kgf load		Rockwell Hardness			Rockwell Superficial Hardness			Shore Hardness (HS)	Tensile Strength [MPa] (Approximate Value)	Rockwell C Scale Hardness (HRC)
Rockwell C hardness (HRC)	Vickers Hardness (HV)	Standard ball	Tungsten carbide ball	HRA	HRB	HRD	15N	30N	45N	Shore Hardness (HS)	Tensile Strength [MPa] (Approximate Value)	Rockwell C Scale Hardness (HRC)
68	940	―	―	85.6	―	76.9	93.2	84.4	75.4	97	―	68
67	900	―	―	85.0	―	76.1	92.9	83.6	74.2	95	―	67
66	865	―	―	84.5	―	75.4	92.5	82.8	73.3	92	―	66
65	832	―	(739)	83.9	―	74.5	92.2	81.9	72.0	91	―	65
64	800	―	(722)	83.4	―	73.8	91.8	81.1	71.0	88	―	64

63	772	―	(705)	82.8	―	73.0	91.4	80.1	69.9	87	―	63
62	746	―	(688)	82.3	―	72.2	91.1	79.3	68.8	85	―	62
61	720	―	(670)	81.8	―	71.5	90.7	78.4	67.7	83	―	61
60	697	―	(654)	81.2	―	70.7	90.2	77.5	66.6	81	―	60
59	674	―	(634)	80.7	―	69.9	89.8	56.6	65.5	80	―	59

58	653	―	615	80.1	―	69.2	89.3	75.7	64.3	78	―	58
57	633	―	595	79.6	―	68.5	88.9	74.8	63.2	76	―	57
56	613	―	577	79.0	―	67.7	88.3	73.9	62.0	75	―	56
55	595	―	560	78.5	―	66.9	87.9	73.0	60.9	74	2075	55
54	577	―	543	78.0	―	66.1	87.4	72.0	59.8	72	2015	54

53	560	―	525	77.4	―	65.4	86.9	71.2	58.5	71	1950	53
52	544	(500)	512	76.8	―	64.6	86.4	70.2	57.4	69	1880	52
51	528	(487)	496	76.3	―	63.8	85.9	69.4	56.1	68	1820	51
50	513	(475)	481	75.9	―	63.1	85.5	68.5	55.0	67	1,760	50
49	498	(464)	469	75.2	―	62.1	85.0	67.6	53.8	66	1,695	49

48	484	451	455	74.7	―	61.4	84.5	66.7	52.5	64	1635	48
47	471	442	443	74.1	―	60.8	83.9	65.8	51.4	63	1580	47
46	458	432	432	73.6	―	60.0	83.5	64.8	50.3	62	1530	46
45	446	421	421	73.1	―	59.2	83.0	64.0	49.0	60	1,480	45
44	434	409	409	72.5	―	58.5	82.5	63.1	47.8	58	1435	44

43	423	400	400	72.0	―	57.7	82.0	62.2	46.7	57	1,385	43
42	412	390	390	71.5	―	56.9	81.5	61.3	45.5	56	1,340	42
41	402	381	381	70.9	―	56.2	80.9	60.4	44.3	55	1,295	41
40	392	371	371	70.4	―	55.4	80.4	59.5	43.1	54	1,250	40
39	382	362	362	69.9	―	54.6	79.9	58.6	41.9	52	1215	39

38	372	353	353	69.4	―	53.8	79.4	57.7	40.8	51	1,180	38
37	363	344	344	68.9	―	53.1	78.8	56.8	39.6	50	1160	37
36	354	336	336	68.4	(109.0)	52.3	78.3	55.9	38.4	49	1115	36
35	345	327	327	67.9	(108.5)	51.5	77.7	55.0	37.2	48	1080	35
34	336	319	319	67.4	(108.0)	50.8	77.2	54.2	36.1	47	1055	34

33	327	311	311	66.8	(107.5)	50.0	76.6	53.3	34.9	46	1025	33
32	318	301	301	66.3	(107.0)	49.2	76.1	52.1	33.7	44	1,000	32
31	310	294	294	65.8	(106.0)	48.4	75.6	51.3	32.7	43	980	31
30	302	286	286	65.3	(105.5)	47.7	75.0	50.4	31.3	42	950	30
29	294	279	279	64.7	(104.5)	47.0	74.5	49.5	30.1	41	930	29

28	286	271	271	64.3	(104.0)	46.1	73.9	48.6	28.9	41	910	28
27	279	264	264	63.8	(103.0)	45.2	73.3	47.7	27.8	40	880	27
26	272	258	258	63.3	(102.5)	44.6	72.8	46.8	26.7	38	860	26
25	266	253	253	62.8	(101.5)	43.8	72.2	45.9	25.5	38	840	25
24	260	247	247	62.4	(101.0)	43.1	71.6	45.0	24.3	37	825	24

23	254	243	243	62.0	100.0	42.1	71.0	44.0	23.1	36	805	23
22	248	237	237	61.5	99.0	41.6	70.5	43.2	22.0	35	785	22
21	243	231	231	61.0	98.5	40.9	69.9	42.3	20.7	35	770	21
20	238	226	226	60.5	97.8	40.1	69.4	41.5	19.6	34	760	20
(18)	230	219	219	―	96.7	―	―	―	―	33	730	(18)

Numbers in bold are based on the table in ASTM E 140 (which was jointly developed by SAE, ASM, and ASTM).
The numbers in parentheses ( ) in the table represent ranges that are rarely used and are provided for reference only.

Steel Hardness Conversion to Rockwell C Scale

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