This value is useful for visualizing how much material remains between the physical hole boundary and the plate edge.
Preliminary Edge Distance Reference
Minimum Ratio
Equivalent Minimum Distance
General Use
1.25 × D
1.25 bolt diameters
Tight preliminary layout reference
1.50 × D
1.50 bolt diameters
Common preliminary reference
1.75 × D
1.75 bolt diameters
Greater edge margin
2.00 × D
2.00 bolt diameters
Conservative preliminary layout
2.50 × D
2.50 bolt diameters
Large edge margin
These ratios are generic planning references, not universal code requirements. Actual minimum edge distances can differ by design standard, hole type, material, fabrication process and loading.
Hole Type Considerations
Standard round holes generally have straightforward edge-distance geometry.
Oversize holes may require different detailing requirements.
Slotted holes require consideration of the slot direction and nearest edge.
Edge distance requirements may differ for different hole types under specific standards.
Cut-edge conditions can affect permissible detailing requirements.
Important Limitations
This tool checks a geometric edge-distance ratio only.
It does not perform a complete bolt connection design.
It does not calculate bearing strength.
It does not calculate tear-out or block-shear capacity.
It does not calculate bolt shear or tension capacity.
It does not determine code-specific minimum edge distances automatically.
It does not verify pitch or gauge distances between multiple holes.
It does not account for every effect of slotted or oversize holes.
It does not assess corrosion allowances or damaged edges.
Engineering warning: Use this calculator for preliminary layout checking only. For structural or safety-critical connections, verify the required edge distance against the applicable design standard and complete connection design.
Frequently Asked Questions
What is bolt hole edge distance?
It is the distance from the center of a bolt hole to the nearest edge of the metal plate.
Why is edge distance important?
Insufficient edge distance can reduce the available material around a hole and may affect bearing, tear-out, block-shear and connection performance.
Does edge distance depend on bolt diameter?
Bolt diameter is an important layout parameter, but the actual requirement also depends on the hole type, material, loading, fabrication and applicable standard.
What happens if the edge distance is too small?
The connection may have insufficient material between the hole and edge, potentially reducing the connection's resistance to local failure modes.
Does this tool check multiple bolt spacing?
No. It focuses on the distance from an individual bolt hole to the nearest plate edge.
Can I use a different minimum edge-distance ratio?
Yes. Enter the required project-specific ratio in the Minimum Edge Ratio field.