Conversion result is the closest match in the reference table — hardness scale conversions are approximate.
| Brinell (HB) | Rockwell C | Rockwell B | Vickers (HV) | Tensile (MPa) |
|---|---|---|---|---|
| 739 | 65 | — | 832 | 2530 |
| 712 | 63 | — | 800 | 2445 |
| 682 | 61 | — | 765 | 2355 |
| 653 | 59 | — | 730 | 2240 |
| 627 | 57 | — | 697 | 2150 |
| 601 | 55 | — | 667 | 2070 |
| 578 | 53 | — | 640 | 1985 |
| 555 | 51 | — | 615 | 1900 |
| 532 | 49 | — | 591 | 1830 |
| 512 | 47 | — | 569 | 1760 |
| 492 | 45 | — | 547 | 1690 |
| 472 | 43 | — | 525 | 1620 |
| 451 | 41 | — | 501 | 1550 |
| 432 | 39 | — | 480 | 1485 |
| 415 | 37 | — | 461 | 1420 |
| 397 | 35 | — | 442 | 1360 |
| 380 | 33 | — | 423 | 1300 |
| 363 | 31 | — | 404 | 1240 |
| 347 | 29 | — | 385 | 1180 |
| 331 | 27 | — | 366 | 1120 |
| 316 | 25 | — | 350 | 1080 |
| 302 | 23 | — | 334 | 1030 |
| 286 | 21 | — | 316 | 980 |
| 271 | 19 | — | 299 | 930 |
| 258 | 17 | — | 284 | 885 |
| 247 | 15 | 100 | 271 | 845 |
| 237 | 13 | 99 | 260 | 810 |
| 226 | — | 98 | 248 | 775 |
| 217 | — | 96 | 238 | 745 |
| 207 | — | 95 | 228 | 710 |
| 197 | — | 93 | 217 | 675 |
| 187 | — | 91 | 206 | 640 |
| 179 | — | 89 | 196 | 615 |
| 170 | — | 87 | 186 | 585 |
| 163 | — | 85 | 178 | 560 |
| 156 | — | 83 | 171 | 535 |
| 149 | — | 81 | 163 | 515 |
| 143 | — | 79 | 156 | 490 |
| 137 | — | 77 | 150 | 470 |
| 131 | — | 75 | 143 | 450 |
| 126 | — | 72 | 137 | 435 |
| 121 | — | 69 | 131 | 415 |
| 116 | — | 67 | 126 | 400 |
| 111 | — | 65 | 121 | 385 |
Hardness testing measures a material's resistance to indentation. The three most common scales for steel are Brinell (HB) — used for annealed and medium-hardness steels, Rockwell C (HRC) — the standard for hardened steels above ~20 HRC, and Vickers (HV) — a universal scale that works across the full range.
Conversion between scales is based on empirical tables (ASTM E140) rather than direct formulas, because each test uses a different indenter geometry and load. The values in this tool are approximate and intended for reference. For critical applications, always test in the required scale directly.
Brinell to Rockwell C conversion is not a simple formula — it is based on empirical data from ASTM E140. For example, 300 HB ≈ 32 HRC, 400 HB ≈ 43 HRC, and 500 HB ≈ 49 HRC. Use this calculator for instant lookup of the closest standard conversion.
All three measure indentation hardness but use different indenters and loads. Brinell (HB) uses a 10mm steel ball, Rockwell C (HRC) uses a diamond cone for hard steels, Rockwell B (HRB) uses a 1/16″ ball for softer steels, and Vickers (HV) uses a diamond pyramid. Each scale suits different hardness ranges.
For carbon and alloy steels, approximate tensile strength (MPa) ≈ 3.45 × Brinell hardness (HB). For example, 200 HB ≈ 690 MPa. This relationship is approximate and varies with steel composition and heat treatment.