Does this calculator determine an ISO 1328 flank tolerance class?

No. It only compares a measured magnitude with a limit supplied from the exact licensed standard,drawing or contract. It does not calculate class limits or recommend a class.

What must match between measured value and limit?

The deviation characteristic,gear scope,evaluation range,filtering,flank/direction,unit and all other governing conditions must be the same. Measurement uncertainty is not included.

Document-controlled comparison — no generated ISO limit

Documented Gear-Deviation Limit Comparator

Compare one measured gear-deviation magnitude with a documented allowable limit for the same characteristic,gear and evaluation conditions. This tool does not calculate or recommend an ISO flank tolerance class.

margin=L−Mutilization=100M/LNo invented ISO table

Documented-limit arithmetic

Measured magnitude M

Documented limit L

Arithmetic comparison

Margin L−M

Utilization 100M/L

Ratio M/L

Measured normalized

Limit normalized

Implemented arithmetic only

margin=L−M
ratio=M/L
utilization=100(M/L)%
comparison: M<L, M=L, or M>L

M and L are nonnegative magnitudes in the same unit. Exact conversions are1mm=1000µm and1in=25400µm. The comparison adds no class,tolerance,rounding or uncertainty rule.

ISO1328 scope checked

ISO1328-1:2013,edition2 establishes a flank-tolerance classification system for manufacturing and conformity assessment of tooth flanks of individual cylindrical involute gears. It defines terms,the class-system structure and allowable values;the edition was confirmed current in2024. The official card does not expose the numerical formulae,tables or rounding clauses,so this page does not reproduce them.

ISO1328-2:2020,edition2 is a separate system for double-flank radial composite deviations and is limited to its stated gear scope. ISO/TR10064-1:2019,edition3 supplements Part1 with measurement practice for pitch,profile,helix and tangential composite characteristics;double-flank testing is excluded there.

Why class calculation was removed

The former page asserted exact clause numbers,base formula coefficients,√2 class scaling,rounding rules and application recommendations without a licensed source. A plausible-looking formula is not proof of ISO conformity. Exact class limits must be taken from the licensed current standard for the actual gear geometry and deviation characteristic.

No conformity or class selection

Even a numerical M≤L comparison is not a complete conformity statement when measurement uncertainty,traceability,sampling,filtering or decision rules matter. This page does not recommend a class or application. Preserve the source row,edition,drawing and measurement report with the result.