With various industry standards for hardness testing of engineering materials, it can be difficult to interpret between different reference codes and hardness units.
This guide aims to simplify the cross-referencing between the 4 most commonly used Hardness Scales.
| Hardness Scale Name | Vickers Pyramid Number | Rockwell | BRINELL | U.T.S. | 
| Reference Code | VPN | HRC | HB | N/mm2 | 
| Units | DPH HV/10 | C | BHN 3000kg | MPa | 
| 1076 | 70 | |||
| 1004 | 69 | |||
| 940 | 68 | |||
| 900 | 67 | |||
| 865 | 66 | |||
| 832 | 65 | 739 | ||
| 800 | 64 | 722 | ||
| 772 | 63 | 705 | ||
| 746 | 62 | 688 | ||
| 720 | 61 | 670 | ||
| 697 | 60 | 654 | 2206 | |
| 674 | 59 | 634 | 2137 | |
| 653 | 58 | 615 | 2069 | |
| 633 | 57 | 595 | 2000 | |
| 613 | 56 | 577 | 1944 | |
| 595 | 55 | 560 | 1889 | |
| 577 | 54 | 543 | 1834 | |
| 560 | 53 | 523 | 1772 | |
| 544 | 52 | 512 | 1689 | |
| 528 | 51 | 496 | 1648 | |
| 513 | 50 | 481 | 1607 | |
| 498 | 49 | 469 | 1565 | |
| 484 | 48 | 455 | 1524 | |
| 471 | 47 | 443 | 1496 | |
| 458 | 46 | 432 | 1462 | |
| 446 | 45 | 421 | 1420 | |
| 434 | 44 | 409 | 1379 | |
| 423 | 43 | 400 | 1351 | |
| 412 | 42 | 390 | 1317 | |
| 402 | 41 | 381 | 1289 | |
| 392 | 40 | 371 | 1255 | |
| 382 | 39 | 362 | 1220 | |
| 372 | 38 | 353 | 1193 | |
| 363 | 37 | 344 | 1165 | |
| 354 | 36 | 336 | 1138 | |
| 345 | 35 | 327 | 1103 | |
| 336 | 34 | 319 | 1076 | |
| 327 | 33 | 311 | 1048 | |
| 318 | 32 | 301 | 1014 | |
| 310 | 31 | 294 | 993 | |
| 302 | 30 | 286 | 965 | |
| 294 | 29 | 279 | 945 | |
| 286 | 28 | 271 | 917 | |
| 279 | 27 | 264 | 889 | |
| 272 | 26 | 258 | 869 | |
| 266 | 25 | 253 | 855 | |
| 260 | 24 | 247 | 834 | |
| 254 | 23 | 240 | 814 | |
| 248 | 22 | 234 | 793 | |
| 243 | 21 | 228 | 772 | |
| 238 | 20 | 222 | 752 | |
| 234 | 19 | 218 | 738 | |
| 230 | 18 | 214 | 731 | |
| 226 | 17 | 210 | 717 | |
| 222 | 16 | 208 | 703 | |
| 217 | 15 | 205 | 690 | |
| 213 | 14 | 203 | 683 | |
| 208 | 13 | 200 | 676 | |
| 204 | 12 | 195 | 662 | |
| 200 | 11 | 193 | 655 | |
| 196 | 10 | 190 | 641 | |
| 192 | 9 | 185 | 627 | |
| 188 | 8 | 180 | 607 | |
| 184 | 7 | 176 | 593 | |
| 180 | 6 | 172 | 579 | |
| 176 | 5 | 169 | 572 | |
| 172 | 4 | 165 | 558 | |
| 168 | 3 | 162 | 545 | |
| 164 | 2 | 159 | 538 | |
| 160 | 1 | 156 | 524 | |
| 156 | 0 | 153 | 517 |