Look up the tabulated fine, medium, or coarse clearance-hole diameter for a metric thread.
Set the inputs and run the calculation.
Look up the tabulated clearance-hole diameter for a metric bolt.
Thread nominal diameter and fine, medium or coarse series select the hole size.
The hole series is an assembly choice: fine reduces positional and radial play, coarse tolerates more manufacturing and coating variation. A larger hole does not automatically increase capacity; it mainly reduces locating accuracy.
The ISO table provides three series: fine for little play, medium for general use and coarse for positional error or coatings.
For M10 the medium series gives more assembly clearance than the fine series; final choice depends on position tolerance and bearing area.
Sources and limits: ISO 273 tabulated clearance-hole diameters; check edge distance, washer and joining process separately.
Look up the tabulated clearance-hole diameter for a metric bolt.
This calculator represents a clearly bounded technical relationship between the displayed quantities. The definition helps put inputs into the same reference state before interpreting the result.
The ISO table provides three series: fine for little play, medium for general use and coarse for positional error or coatings.
Thread nominal diameter and fine, medium or coarse series select the hole size. The hole series is an assembly choice: fine reduces positional and radial play, coarse tolerates more manufacturing and coating variation. A larger hole does not automatically increase capacity; it mainly reduces locating accuracy.
Select the bolt's nominal thread diameter and the desired hole series (fine, medium or coarse). The calculator returns the tabulated ISO 273 clearance-hole diameter.
For M10 the medium series gives more assembly clearance than the fine series; final choice depends on position tolerance and bearing area.
The hole series is an assembly choice: fine reduces positional and radial play, coarse tolerates more manufacturing and coating variation. A larger hole does not automatically increase capacity; it mainly reduces locating accuracy. Read the result as a model value for the selected operating point and check units, sign, order of magnitude and application boundary conditions.
Diameter in millimetres.
Specifying hole diameters on manufacturing drawings, or checking whether an existing hole matches a planned bolt size and assembly requirement.
ISO 273 tabulated clearance-hole diameters; check edge distance, washer and joining process separately.
Common mistake: Don't automatically pick the coarse series to ease assembly – excess clearance reduces centering and can compromise positional accuracy in transverse-load joints. Check edge distance and head/nut bearing area separately, especially with thin sheet or tight hole patterns.
The medium series is a sensible starting point for most general machine-building joints; fine suits position-critical joints, coarse suits tolerant or coated joints.
Defined clearance is needed so the bolt can actually be assembled despite manufacturing and positional tolerances of the hole.
No, ISO 273 tabulates the common metric thread sizes; special sizes or requirements need a separate determination.
The calculator supports hole selection for general-purpose bolted assemblies. Medium is often a useful starting point; fine reduces assembly play while coarse gives more positional allowance.
Special applications require a design-specific hole selection. Also check bearing area, edge distance, assembly clearance, coatings, and possible interference with the under-head fillet.