Hardness Conversion Calculator

Work out hardness conversion instantly with clear inputs, formula shown and shareable results.

About Hardness Conversion Calculator

Hardness scales measure different indentation geometries, so conversion is empirical rather than exact. Below about 300 HB Vickers and Brinell agree within a few percent, so HV is taken as 1.05 x HB, while Rockwell C is interpolated from the standard conversion table. Tensile strength for steel follows the long-established 3.45 x HB relation in megapascals.

Formulas

Vickers relation

HV = about 1.05 x HB for HB below 300

Tensile estimate

UTS MPa = 3.45 x HB (carbon and alloy steels)

Worked example

With the default values below, Hardness Conversion Calculator returns Brinell hardness of 200. Change any input above and every figure here is recalculated in your browser.

Inputs used

Measured hardness valueminimum 1: 200
Scale of measurementone of Brinell (HB), Vickers (HV), Rockwell C (HRC): Brinell (HB)

Results

Brinell hardness: 200 HB
Vickers hardness: 210 HV
Rockwell C hardness: 14.0 HRC
Approximate tensile strength: 690 MPa

Step by step

1Values used
2Vickers relation
3Tensile estimate
4Brinell hardness= 200 HB
5Vickers hardness= 210 HV
6Rockwell C hardness= 14.0 HRC
7Approximate tensile strength= 690 MPa

Assumptions and limits

The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Preliminary estimate only. Hardness conversions are approximate; use the standard conversion tables for the specific material and report the scale actually measured.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Preliminary estimate only. Hardness conversions are approximate; use the standard conversion tables for the specific material and report the scale actually measured.

Frequently Asked Questions

How is the Hardness Conversion figure worked out?

HV = about 1.05 x HB for HB below 300. Hardness scales measure different indentation geometries, so conversion is empirical rather than exact.

How reliable are these conversions?

Within roughly plus or minus 5 percent for wrought carbon and alloy steels. They should not be applied to cast iron, austenitic stainless, non-ferrous alloys or case-hardened surfaces.

What values do I need to enter?

This calculator takes 2 inputs: Measured hardness value, Scale of measurement. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.