H7/g6 Fit Explained: Limits, Clearance and Typical Use

H7/g6 combines a hole tolerance zone H7 with a shaft tolerance zone g6. In the ISO hole-basis system, an H hole has zero lower deviation, while a g shaft sits below the basic size.

That geometry normally produces a clearance fit. The actual minimum and maximum clearance depend on the nominal diameter because the ISO tolerance width changes with the dimensional step.

Minimum clearance is the smallest hole limit minus the largest shaft limit. Maximum clearance is the largest hole limit minus the smallest shaft limit.

For a specific nominal diameter, calculate the four limit sizes first. Do not reuse a tolerance value from a different diameter range.

H7/g6 is commonly considered when a controlled running or locating clearance is wanted without intentional interference. The correct fit still depends on load, speed, lubrication, temperature, manufacturing capability and assembly requirements.

• Use the calculator for the exact nominal size.
• Check thermal growth where temperature changes are meaningful.
• Treat fit selection as a design decision, not only a table lookup.