Hardness Conversion Calculator

What Is the Hardness Conversion Calculator?

The Hardness Conversion Calculator converts steel hardness between four common scales: Brinell (HB), Rockwell C (HRC), Rockwell B (HRB), and Vickers (HV). Engineers, metallurgists, and quality inspectors use hardness values to verify material properties, compare specifications, and interpret test certificates from different laboratories.

Because each scale uses different indentor shapes, loads, and measurement methods, there is no exact mathematical formula between them. This tool uses a standard industry conversion table with approximate values derived from extensive experimental data.

How to Use This Calculator

1. Select input scale: Choose HB, HRC, HRB, or HV.
2. Enter hardness value: Type the number from your test report.
3. View all scales: See equivalent values on all four hardness scales.
4. Read details: Check the matched table row and conversion notes.

Hardness Scales Explained

Brinell (HB): Uses a hardened steel or carbide ball pressed into the material surface. Common for castings, forgings, and softer metals. Reported as HB or BHN.

Rockwell C (HRC): Uses a diamond cone indentor with a major load. Standard for hardened steel, tool steel, and heat-treated components. Typical range is about $20$ to $70$ HRC.

Rockwell B (HRB): Uses a $1/16$ inch steel ball. Used for softer metals like mild steel, brass, and aluminum alloys.

Vickers (HV): Uses a diamond pyramid indentor. Works across a wide hardness range and is common in research and microhardness testing.

Example Conversion

A steel sample with $300$ BHN converts to approximately $32$ HRC, $107$ HRB, and $303$ HV. Enter $300$ with Brinell selected to see all equivalent values instantly.

For Brinell hardness calculations from test data, see our Brinell Hardness Calculator. For other material properties, try the Unit Converter.