Does the class code alone give all minimum properties?

No. It encodes nominal strength relationships. Minimum tensile, yield/proof, proof-load, elongation and hardness requirements must be taken from the exact applicable ISO 898-1 row, including diameter and product conditions.

Does this page calculate proof load?

No. The previous proof-load lookup was removed because it mixed an out-of-scope size table with incomplete diameter-dependent property data.

Can the class decoder select a bolt for an application?

No. Selection requires complete joint design, environment, temperature, manufacturing and governing-code checks.

Standards notation tool

ISO 898-1 Property-Class Designation Decoder

Decode the nominal meaning of a class code. This is not a table of minimum properties, proof load, hardness or application suitability.

ISO 898-1:2013 scopeNominal code onlyNo proof-load lookup

Designation meaning

Nominal tensile-strength code x·100

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Nominal ratio code y/10

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Coded nominal product x·y·10

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Selected designation

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Code arithmetic

class x.y → nominal Rm code=x·100 MPa; nominal ratio code=y/10; coded product=x·y·10 MPa

For 8.8 this reads 800 MPa, ratio 0.8 and coded product 640 MPa. These explain the designation; they do not replace the standard’s minimum-property tables.

Current scope

ISO 898-1:2013 was confirmed in 2025 and is marked for revision. Its official scope covers carbon/alloy-steel fasteners M1.6–M39 at 10–35 °C and excludes shear resistance, fatigue and torque/clamp performance.

Removed unsupported outputs

The prior page extended to M48 and generated proof load, ultimate load, proof stress, elongation, hardness and application advice from an incomplete table. Exact values can vary with diameter and product conditions and require the licensed standard. Generic 75–90% preload advice and unrelated ISO links were also removed.