Steel Hardness Converter

• Rockwell C (HRC) — 20–70 typical range; preferred for hardened steels.
• Brinell (HB) — 100–650 typical range; ideal for unfinished or coarse-grained material.
• Vickers (HV) — 100–1000 typical range; works across the full hardness spectrum and on thin sections.

Conversions are approximations defined by ASTM E140. They are most accurate for non-austenitic carbon and alloy steels; readings on austenitic stainless, soft non-ferrous metals, and case-hardened layers should be treated with caution.

Rockwell C is the workhorse for finished tool steels and hardened components. Brinell is used on as-rolled bar, castings, and forgings where the indentation is large enough to average out surface variation. Vickers is preferred for thin sections, surface layers, and when comparing materials across very different hardness levels — its diamond pyramid leaves a small, geometrically similar indent that scales reliably.