Why does the bearing value change when I change the plate thickness?

Bearing and tearout are limits on the connected material, not the bolt: 1.2/1.8 × d × t × F_u and 0.6/0.9 × l_c × t × F_u. A thin ply governs long before the bolt does.

Does it handle oversized or slotted holes?

No — standard holes only. Oversized and slotted holes carry their own slip and bearing multipliers in Specification Chapter J; apply them by hand or use the full Spec.

Can I sum this for a bolt group?

Only if every bolt sees the same load. Eccentric groups, prying and block shear need a real connection check; this page gives you the single-bolt building block and shows its work.

Structural Bolt Capacity Calculator — ASD/LRFD Tension, Shear, Bearing, Tearout

Bolt group / ASTM Bolt diameter d (in) Shear planes Threads

Connected material F_u (ksi) Thinner ply thickness t (in) Clear dist. to edge/hole l_c (in, optional)

Formula & assumptions

Coefficients per AISC Basic Design Values (ANSI/AISC 360-22): tension 0.38/0.56 F_ub A_b, shear 0.23/0.34 F_ub A_b per plane (×1.25 for X), bearing 1.2/1.8 d t F_u, tearout 0.6/0.9 l_c t F_u, slip resistance 0.12/0.18 F_ub A_b (Class A, STD holes, per slip plane). Does not check spacing, edge distance, block shear, or hole-type multipliers (Class B, OVS/SSL/LSL) - see AISC Specification Chapter J. Bolt capacity governs by the lesser of bearing and tearout. Single-bolt values only — does not sum a bolt group and does not select bolt size or grade.

What this calculator does

Quick ASD and LRFD values for one bolt: tension, shear per plane, bearing, tearout and slip resistance, using the coefficients on AISC's Basic Design Values card for ANSI/AISC 360-22. Pick the bolt group, diameter, shear planes and threads condition, enter the connected material's F_u and thickness, and every governing number prints with the formula beside it. It is a preliminary-sizing and field-check tool, not a connection design.

Worked example

3/4" A325, threads included, single shear: A_b = 0.442 in², F_ub = 120 ksi. Shear = 0.23 × 120 × 0.442 = 12.2 kips ASD, 0.34 × 120 × 0.442 = 18.0 kips LRFD. Tension = 20.2 kips ASD, 29.7 kips LRFD.

Common questions

Why does the bearing value change when I change the plate thickness?: Bearing and tearout are limits on the connected material, not the bolt: 1.2/1.8 × d × t × F_u and 0.6/0.9 × l_c × t × F_u. A thin ply governs long before the bolt does.
Does it handle oversized or slotted holes?: No — standard holes only. Oversized and slotted holes carry their own slip and bearing multipliers in Specification Chapter J; apply them by hand or use the full Spec.
Can I sum this for a bolt group?: Only if every bolt sees the same load. Eccentric groups, prying and block shear need a real connection check; this page gives you the single-bolt building block and shows its work.

Verify with project engineer, contract documents, and applicable code/specification. Preliminary/field-reference values only — not a substitute for a licensed engineer’s design. Does not check bolt spacing, edge distance, block shear, prying action, weld access holes, ply-thickness limits, or any other requirement of a complete connection design — see AISC Specification Chapter J.

Bolt capacity (ASD/LRFD)

What this calculator does

Worked example

Common questions

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