--- type: "fit" designation: "H7/h6" hole: "H7" shaft: "h6" basis: "both" classification: "clearance" role: "Locational clearance. Assembles by hand, no free movement intended." size_count: 13 standard: "ISO 286-1:2010, ISO 286-2:2010" verified: "August 1, 2026" url: https://shopmath.org/fits/h7-h6 --- # H7/h6 Fit — ISO 286 Clearance Fit Limits by Nominal Size H7/h6 is a clearance fit: at 25 mm nominal it gives 0 to 34 µm clearance. Locational clearance. Assembles by hand, no free movement intended. The hole is always larger than the shaft — the parts always assemble with a gap. - **Designation**: H7/h6 - **Hole tolerance**: H7 - **Shaft tolerance**: h6 - **Basis**: both basis - **Classification**: Clearance fit - **Typical use**: Locational clearance. Assembles by hand, no free movement intended. - **Standard**: ISO 286-1:2010, ISO 286-2:2010 ## H7/h6 Hole and Shaft Limits by Nominal Size Limits in millimetres, clearances in micrometres. A negative clearance is interference — the shaft is larger than the hole and assembly needs force, heat or cold. | Nominal size | Hole min (mm) | Hole max (mm) | Shaft min (mm) | Shaft max (mm) | Min clearance (µm) | Max clearance (µm) | Result | | --- | --- | --- | --- | --- | --- | --- | --- | | 5 mm | 5.000 | 5.012 | 4.992 | 5.000 | 0 | 20 | Clearance | | 6 mm | 6.000 | 6.012 | 5.992 | 6.000 | 0 | 20 | Clearance | | 8 mm | 8.000 | 8.015 | 7.991 | 8.000 | 0 | 24 | Clearance | | 10 mm | 10.000 | 10.015 | 9.991 | 10.000 | 0 | 24 | Clearance | | 12 mm | 12.000 | 12.018 | 11.989 | 12.000 | 0 | 29 | Clearance | | 16 mm | 16.000 | 16.018 | 15.989 | 16.000 | 0 | 29 | Clearance | | 20 mm | 20.000 | 20.021 | 19.987 | 20.000 | 0 | 34 | Clearance | | 25 mm | 25.000 | 25.021 | 24.987 | 25.000 | 0 | 34 | Clearance | | 30 mm | 30.000 | 30.021 | 29.987 | 30.000 | 0 | 34 | Clearance | | 40 mm | 40.000 | 40.025 | 39.984 | 40.000 | 0 | 41 | Clearance | | 50 mm | 50.000 | 50.025 | 49.984 | 50.000 | 0 | 41 | Clearance | | 80 mm | 80.000 | 80.030 | 79.981 | 80.000 | 0 | 49 | Clearance | | 100 mm | 100.000 | 100.035 | 99.978 | 100.000 | 0 | 57 | Clearance | ## Fits Related to H7/h6 Fits that share the H7 hole or the h6 shaft — the alternatives to reach for when H7/h6 is too tight or too loose. | Fit | Classification | Basis | Typical use | | --- | --- | --- | --- | | [G7/h6](https://shopmath.org/fits/g7-h6.md) | Clearance | shaft basis | Sliding, shaft basis. The h6 shaft is the reference and the hole carries the clearance. | | [H7/g6](https://shopmath.org/fits/h7-g6.md) | Clearance | hole basis | Sliding. Locates accurately, still moves and turns freely. | | [H7/p6](https://shopmath.org/fits/h7-p6.md) | Interference | hole basis | Locational interference. Rigid location in steel without the load capacity of a drive fit. | | [H7/r6](https://shopmath.org/fits/h7-r6.md) | Interference | hole basis | Medium drive. The joint itself carries load. | | [P7/h6](https://shopmath.org/fits/p7-h6.md) | Interference | shaft basis | Locational interference, shaft basis. | | [H7/k6](https://shopmath.org/fits/h7-k6.md) | Transition | hole basis | Locational transition. Accurate location, assembles with light force. | | [H7/m6](https://shopmath.org/fits/h7-m6.md) | Transition | hole basis | Locational transition, tighter than k6. | | [H7/n6](https://shopmath.org/fits/h7-n6.md) | Transition | hole basis | Tight transition. Usually a press job. | | [K7/h6](https://shopmath.org/fits/k7-h6.md) | Transition | shaft basis | Locational transition, shaft basis. | | [N7/h6](https://shopmath.org/fits/n7-h6.md) | Transition | shaft basis | Tight transition, shaft basis. | ## Sources and Method for the H7/h6 Fit ### H7/h6 limits - **Source**: computed from the compiled ISO 286 tables: ISO 286-1 IT grades and ISO 286-2 fundamental deviations, compiled from saucecode/ISO286 (LGPL-2.1) and parkergreene/isofits (MIT), cross-checked cell-for-cell - **Method**: computed - **Verified against**: parkergreene/isofits ISO 286-2 limit tables (MIT); ISO 286-1 formula harness — 2067 checks passed ### Assumptions - Values are the ISO 286-2 tabulated limits, not the ISO 286-1 formula: the formula deviates from the table by up to 13.26% and is carried only as a validation harness. - Limits are at 20 °C, the ISO 1 reference temperature. Clearance is the assembled gap before any thermal or load effect. - Dataset scope: COMPILED not computed: the ISO 286-1 formula deviates up to 13.26% from the table and is used only as a harness (warn >5%, fail >15%). EXCLUDED: shaft/hole letters s, t, u and the fits H7/s6, H7/t6, H7/u6 — no free source and an undetermined step constant in the formula. **Data last verified**: August 1, 2026 ## Common Questions About the H7/h6 Fit ### What kind of fit is H7/h6? H7/h6 is a clearance fit on a both basis. The hole is always larger than the shaft — the parts always assemble with a gap. Locational clearance. Assembles by hand, no free movement intended. ### What is the clearance on a 25 mm H7/h6 fit? At 25 mm nominal, H7/h6 gives 0 to 34 µm clearance. The hole runs 25.000 to 25.021 mm and the shaft 24.987 to 25.000 mm. ### What hole and shaft tolerances make up H7/h6? H7/h6 pairs a H7 hole with a h6 shaft. On a both basis, the hole carries the zero-deviation member and the other side is moved to set the fit. ## Related pages - Hole tolerance: [H7 limits by size](https://shopmath.org/fits/h7.md) - Shaft tolerance: [h6 limits by size](https://shopmath.org/fits/h6.md) - All fits and tolerances: [ISO 286 fit reference](https://shopmath.org/fits.md) - Full grade table: [ISO 286 tolerance chart](https://shopmath.org/charts/iso-tolerances.md) --- *Source: [ShopMath](https://shopmath.org/fits/h7-h6) — data verified August 1, 2026. Reference data; verify against the governing standard before manufacture.*