Free Steel Connection Design Calculator

The calculator runs the full SkyCiv Connection Design engine. You choose a configuration from the template library, define the members and the connecting elements, set the bolts or welds, and enter the design actions.

It reports a utilization ratio against each limit state rather than a single pass or fail, so you can see which check is close to governing and what to change if it is not. Design engineers, contractors and fabricators use it, and so do students working on coursework.

The calculator designs to AISC 360-16 in ASD or LRFD, and to AS 4100:2020. AISC work can be done in Imperial or Metric units, and AS 4100 runs in Metric.

Pick the design method before you enter loads. LRFD takes factored loads against design strength and ASD takes service loads against allowable strength, and the calculator cannot tell which you typed.

The library holds over 80 pre-configured connection types. Most are available framing to a column flange, a column web or another beam’s web, which is where the count comes from. They are grouped by the members being joined.

The largest group, covering beam to column and beam to beam framing:

• Shear connections: single angle, double angle, single plate (shear tab or fin plate), double plate, end plate and directly welded web.
• Shear plus axial connections: double angle, single plate, end plate and directly welded web.
• Moment connections: welded flanges, flange plate, flush end plate and extended end plate.
• Splices: column splice and beam splice, both using flange and web plates.

For a beam framing into a hollow structural section column:

• Shear: single angle, double angle, single plate, single WT and seat angle.
• Shear plus axial: single plate.
• Moment: flange plate.

Channel sections are covered for shear, using a directly welded web or a single plate.

The bracing group covers the gusseted joints in a braced frame:

• Vertical brace: single plate, double angle, end plate or directly welded to the column, each with a lower brace only, an upper brace only, or both.
• Chevron brace: directly welded gusset plate.
• Knee brace: directly welded gusset plate.
• Truss brace: the knee and chevron gusset configurations, applied to a truss node.
• Horizontal brace: single plate or single angle to the support, with or without a column at the joint.

Bracing is available under AISC only.

AS 4100:2020 covers shear connections between I-sections: the web side plate, flexible end plate, single angle and double angle.

Wide Flange, HSS, WT, L and 2L profiles are available under AISC, and Universal Beams and Universal Columns under AS 4100. Standard steel grades for members, plates and fasteners are pre-loaded, and you can enter your own Fy and Fu where a grade is not listed.

Every interface can be bolted or welded. For the fastener side on its own, there is a bolt calculator and a weld calculator.

Work through the tabs in this order:

1. Code and category: pick AISC 360-16 or AS 4100:2020, the units, and the members being joined.
2. Configuration: choose the connection type from the template cards.
3. Assembly: set the supported and supporting members, their sections and grades.
4. Connection: the plate or angle geometry.
5. Fixtures: bolt grade, diameter, hole type and layout, or weld size and electrode strength.
6. Loads: the design actions, matched to the method you picked.

Then run the design checks. Anything missing from an earlier tab is flagged rather than silently defaulted, and the detailing limitation table flags a connection that satisfies every strength calculation but still cannot be fabricated or erected.

The free calculator is the same software and carries the same connection library. What it limits is how much you can change and how much of the results you see.

• Solves: a free user gets 20 design check runs per week.
• Results: the demand is shown for every check, but the capacity and the ratio are locked on the back half of the design checks and the detailing limits. An odd count rounds the shown half down, so a section holding a single check is locked outright.
• Report: the detailed calculation report is not produced.
• Files: connection files cannot be saved or loaded.
• Inputs: bolt hole type, section shape, member, bolt and weld materials, bolt diameter, connection elements and weld sides stay at their defaults and are marked PRO.

A free account is what lets you save and reload your work.

The full SkyCiv Connection Design module unlocks all of the above. Its report writes out every calculation step with the equation, design table and clause it came from in AISC 360-16 or AS 4100:2020, so the working can be read line by line instead of reverse-engineered from a number.

It also runs the detailing and clash checks before the solve, produces CloudCAD detail drawings alongside the calculation report, and exports 3D connection geometry directly to IFC. It runs entirely in the cloud, with no downloads, updates or IT setup.

The steel connection design software page sets out the full feature list and pricing options.

• Beam Splice Connection Calculator
• Bolt Calculator
• Bolted Connection Design
• Bolted Splice Connection Calculator
• Chevron Brace Connection Calculator
• Column Splice Connection Calculator
• Double Angle Connection Calculator
• End Plate Connection Calculator
• Flange Plate Connection Calculator
• Horizontal Bracing Connection Calculator
• Knee Brace Connection Calculator
• Moment Connection
• Shear Connection Calculator
• Single Angle Connection Calculator
• Single Plate Connection Calculator
• SkyCiv Connection Design Vs. Idea Statica
• SkyCiv Connection Design Vs. Ram Connection
• Vertical Bracing Connection Calculator
• Weld Calculator
• Welded Connection Design