Tools · Structural

Weld Sizing & Strength Calculator

Check a simple linear fillet weld's allowable capacity, or analyze an eccentrically-loaded weld group by the AISC elastic (weld-treated-as-a-line) method.

⚠ Disclaimer: Use at Your Own Risk This tool is provided "as is," for general engineering reference and educational purposes only, with no warranty of any kind. Allowable stress uses the AISC 360 ASD fillet weld provision (0.30×F_EXX on the effective throat); it does not implement LRFD, base metal shear rupture/yield checks, or minimum/maximum weld size rules. The eccentric weld group tab uses the classical elastic (line) method only, evaluated at weld-segment endpoints; it does not implement the more accurate but iterative instantaneous-center-of-rotation (IC) method, which generally permits smaller welds. Both are simplified structural calculations, not a substitute for a licensed engineer's connection design. Jeffrium and Jeffrey Sowards assume no liability for decisions, designs, or outcomes based on this tool's output. Do not use these results as the sole basis for a structural connection design; verify independently. Use of this tool is entirely at your own risk.

Weld Geometry

Leg Size, a (in)

Weld Length, L (in)

Electrode / Allowable Stress

Electrode Classification

Allowable Shear Stress, τ (ksi)

ASD allowable = 0.30 × F_EXX, per AISC 360 Table J2.5.

Applied Load (optional)

Applied Force, P (kips)

Weld Capacity

t = 0.707a · F = t × L × τ

Weld Group Shape

Template

Depth, d (in)

Width, b (in) (if applicable)

Coordinates are in inches, in any consistent local system; the tool computes the centroid for you.

Applied Load

F_x (kips)

F_y (kips)

Load Point x (in)

Load Point y (in)

The load point is where the applied force actually acts (e.g. at a bracket's bolt line); it doesn't need to line up with the weld group.

Weld Size & Electrode

Leg Size, a (in)

Electrode

Allowable Shear Stress, τ (ksi)

Weld Group Diagram

Centroid, applied load, and the governing point marked

Elastic Method Results

f = √[(F_x/L − My/J)² + (F_y/L + Mx/J)²]

Need the instantaneous-center method, or a full connection design?

The IC method, base metal checks, bolted-plus-welded combinations, and full connection design packages are exactly the kind of structural work Jeffrium takes on.

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