Hardness converter
Enter a hardness on any scale to see the Rockwell, Vickers and Brinell equivalents for steel, plus approximate tensile strength.
Which scale?
HRC (Rockwell C, diamond cone, 150 kgf): hardened steel, about 20–70 HRC.
HRB (Rockwell B, ball, 100 kgf): soft steel, brass and aluminium, below 20 HRC.
HB (Brinell, 10 mm ball): castings, forgings and bar stock up to about 650 HB.
HV (Vickers, diamond pyramid): any hardness, thin parts and case depth.
Rules of thumb
Steel tensile strength ≈ 3.4 × HB in MPa.
Above 45 HRC, look at CBN or ceramic. HSS tools themselves reach 62–67 HRC.
Conversions are approximate and apply to carbon and alloy steels. They don’t apply to austenitic stainless or non-ferrous metals.
Rockwell C table
| HRC | HV | HB | 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 | – |
| 58 | 653 | 615 | – |
| 57 | 633 | 595 | – |
| 56 | 613 | 577 | – |
| 55 | 595 | 560 | – |
| 54 | 577 | 543 | – |
| 53 | 560 | 525 | – |
| 52 | 544 | 512 | – |
| 51 | 528 | 496 | – |
| 50 | 513 | 481 | – |
| 49 | 498 | 469 | – |
| 48 | 484 | 455 | 1530 |
| 47 | 471 | 443 | 1510 |
| 46 | 458 | 432 | 1480 |
| 45 | 446 | 421 | 1440 |
| 44 | 434 | 409 | 1400 |
| 43 | 423 | 400 | 1360 |
| 42 | 412 | 390 | 1320 |
| 41 | 402 | 381 | 1290 |
| 40 | 392 | 371 | 1260 |
| 39 | 382 | 362 | 1230 |
| 38 | 372 | 353 | 1190 |
| 37 | 363 | 344 | 1160 |
| 36 | 354 | 336 | 1130 |
| 35 | 345 | 327 | 1100 |
| 34 | 336 | 319 | 1080 |
| 33 | 327 | 311 | 1050 |
| 32 | 318 | 301 | 1020 |
| 31 | 310 | 294 | 990 |
| 30 | 302 | 286 | 970 |
| 29 | 294 | 279 | 950 |
| 28 | 286 | 271 | 920 |
| 27 | 279 | 264 | 900 |
| 26 | 272 | 258 | 880 |
| 25 | 266 | 253 | 870 |
| 24 | 260 | 247 | 850 |
| 23 | 254 | 243 | 830 |
| 22 | 248 | 237 | 800 |
| 21 | 243 | 231 | 780 |
| 20 | 238 | 226 | 760 |
Rockwell B table
| HRB | HV | HB | MPa ≈ |
|---|---|---|---|
| 100 | 269 | 255 | 873 |
| 99 | 261 | 248 | 853 |
| 98 | 253 | 241 | 824 |
| 97 | 247 | 235 | 794 |
| 96 | 241 | 229 | 775 |
| 95 | 228 | 217 | 745 |
| 94 | 223 | 212 | 716 |
| 93 | 218 | 207 | 696 |
| 91 | 208 | 197 | 667 |
| 89 | 197 | 187 | 637 |
| 87 | 189 | 179 | 608 |
| 85 | 179 | 170 | 559 |
| 83 | 172 | 163 | 539 |
| 81 | 165 | 156 | 530 |
| 79 | 157 | 149 | 500 |
| 77 | 150 | 143 | 481 |
| 74 | 144 | 137 | 471 |
| 72 | 138 | 131 | 461 |
| 69 | 133 | 126 | 451 |
| 67 | 127 | 121 | 431 |
| 64 | 122 | 116 | 422 |
| 61 | 117 | 111 | 402 |
HRC values per ASTM E140 (non-austenitic steels), HB with a tungsten carbide ball. HRB values per BS 860 and ASTM E140. Printable version: hardness conversion chart (A3 PDF).
A guide only. These tools and figures are general starting points, not a guarantee for your job. Results depend on your machine, setup, material and tooling, so always check against the tool maker’s data, and talk to a Teravin sales engineer to make sure it’s right for your application. Call +61 8 9345 2099 or ask us. See our terms of use.
