ISO 286 fits visualizer.
Drag the controls. Watch the shaft and hole tolerance bands shift on the SVG. Live worst-case clearance or interference, the fit category verdict, and the exact size limits — all per ISO 286-1:2010.
Fit configuration
Values are computed live from ISO 286-1 IT grade and fundamental deviation formulas. Verify on the ISO 286 fits chart.
How to read the diagram
The horizontal black line is the nominal diameter — the basic size called out on the drawing (25 mm in the default view). All tolerances are expressed as deviations relative to this line in micrometres (µm).
The blue band shows where the hole can sit. For uppercase letter codes (H, G, F, etc.), the band is always above or astride the zero line — the hole is "at or larger than nominal". The red band shows where the shaft can sit. Lowercase shaft codes (h, g, k, n, p, etc.) sit above, astride, or below the zero line depending on the letter.
The relationship between the bands tells you the fit category at a glance:
- Hole band entirely above shaft band → clearance fit. Shaft is always smaller, parts assemble loosely.
- Bands overlap → transition fit. Could be clearance or interference depending on actual sizes within tolerance.
- Shaft band entirely above hole band → interference fit. Shaft is always larger, requires press or shrink to assemble.
The exact numbers below the diagram show maximum and minimum clearance (or interference) for the selected combination, computed from ISO 286-1 IT grade and fundamental deviation formulas. For the complete reference of every fit and every diameter range, see the ISO 286 fits chart. For interactive computation including press-fit hoop stress, see the ISO 286 Fits Calculator and the Press / Interference Fit Calculator.