Rivet Size - Diameter, Length, and Hole Size

A rivet size calculator is a construction and DIY tool that turns the thickest plate in a joint, the other plates stacked behind it, the rivet material, and an applied shear load into the rivet shank diameter, the rivet body length, and the clearance hole size for a solid or blind rivet. It is useful when you need a defensible fastener size for sheet metal work, HVAC brackets, fence repair, trailer panels, and small fabrication jobs where a bolted joint is not practical.

• • Sheet metal bracket sizing: Pick a rivet diameter and length for joining a metal bracket to a frame on a trailer or gate.
• • HVAC and ductwork seams: Pick a rivet diameter for joining sheet metal duct sections where a screw would catch on airflow.
• • Fence and gate repair: Pick a rivet diameter and length to replace a stripped or rusted bolt in a fence frame.
• • Sheet metal flashing and trim: Pick a rivet diameter for joining aluminum flashing or trim where the joint needs to stay flush.

The calculator returns the three numbers a fabricator or homeowner needs to actually install a rivet: the shank diameter, the body length, and the hole size.

When the rivet head has to sit flush with the sheet, the Countersink Depth Calculator sizes the countersink angle and depth for the same sheet thickness and fastener diameter.

The calculator takes the thickest plate in the joint and the rivet material, and returns a recommended shank diameter that is at least 3 times the thickest plate, and at least the minimum diameter from a shear strength check using the per-rivet load, the number of rivets, and the rivet material allowable shear stress.

• Thickest plate: Thickness of the thickest single plate, in millimetres. Sets the rule-of-thumb diameter from the Omni Calculator rivet size rule.
• Other plates total: Sum of every other plate in the joint, in millimetres. Added to the thickest plate to set the total clamping thickness.
• Total shear load: Total shear load on the joint, in newtons. Split across the number of rivets for the strength check.
• Rivet material: Stainless, aluminum 6061-T6, or aluminum 5052-H32. Sets the allowable shear stress from the UniPunch chart.
• Recommended diameter: Larger of the rule-of-thumb and shear diameters, rounded up to the nearest 0.5 mm.
• Clearance hole: Recommended diameter plus 0.1 mm for small rivets and 0.2 mm for larger rivets.

The rule-of-thumb and shear diameters are compared, and the larger is rounded up to the next 0.5 mm.

According to Omni Calculator rivet size page, the rivet shank diameter should be about 3 times the thickest plate in the joint, and for general-construction button-head rivets the rivet length should be the total clamping thickness plus 1.5 times the shank diameter.

The same load that drives the rivet shear check also drives a bolt preload check, and the Bolt Torque Calculator sizes the torque for the equivalent bolted joint in the same load range.

Rivet sizing is built from four well documented mechanical rules that cover the cases that come up most often.

Rounding to the nearest 0.5 mm keeps the result inside standard fractional and metric rivet sizes that are actually stocked.

The rivet hole and the bolt hole use the same 0.1 mm to 0.2 mm clearance convention, and the Clearance Hole Calculator returns the clearance hole size for a wide range of bolt and rivet diameters.

Pick the rivet material, enter the thickest plate and the total of the other plates, enter the total shear load, and read the recommended diameter, length, and clearance hole.

1. 1 Pick the rivet material: Select stainless 302/304 annealed, aluminum 6061-T6, or aluminum 5052-H32 so the calculator applies the correct allowable shear stress.
2. 2 Enter the thickest plate: Type the thickness of the thickest single plate in the joint. For a 1.5 mm bracket on a 3.5 mm frame, enter 1.5.
3. 3 Enter the total of the other plates: Type the sum of every other plate in the joint. For a 1.5 mm bracket and a 3.5 mm frame, enter 3.5.
4. 4 Enter the shear load and rivet count: Type the total shear load in newtons and the number of rivets that share it.
5. 5 Read the recommended diameter, length, and hole size: The result panel shows the rule-of-thumb and shear diameters, the recommended diameter rounded to a shelf size, the required rivet length, and the clearance hole size to drill.

A maintenance tech joining a 1.5 mm stainless bracket to a 3.5 mm steel frame with a 2000 N shear load picks stainless, enters 1.5 mm for the thickest plate, 3.5 mm for the other plates, 2000 N for the load, and 2 rivets. The calculator returns a 4.5 mm recommended diameter, an 11.75 mm rivet length, and a 4.7 mm clearance hole.

When the rivet holes are punched instead of drilled, the Punch Force Calculator sizes the punch tonnage for the same sheet thickness and hole diameter.

The result panel returns the three numbers a fabricator and a homeowner need to buy and install a rivet.

• • Three rivet numbers in one view: Returns the rule-of-thumb diameter, the shear-based minimum diameter, and the recommended diameter from the same input set.
• • Real shelf-size rounding: Rounds the recommended diameter up to the next 0.5 mm so the answer matches a real fractional or metric rivet size.
• • Shear strength check: Compares the rule-of-thumb diameter against a minimum diameter from the per-rivet load and the rivet material allowable shear stress.
• • Clearance hole included: Returns the clearance hole size from the standard 0.1 mm to 0.2 mm convention so the drilled hole matches the rivet on the first try.
• • Three rivet materials supported: Supports stainless 302/304 annealed, aluminum 6061-T6, and aluminum 5052-H32 with documented allowable shear stresses of 517 MPa, 207 MPa, and 138 MPa.

The same input set returns a rivet diameter, a rivet length, and a clearance hole, which are the three numbers that show up on a rivet box and a drill bit chart.

When the rivets are laid out in a circle around a hub or a flange, the Bolt Circle Calculator returns the bolt circle diameter and the equal-spaced hole coordinates.

A few material and design factors shift the actual rivet size away from the rule-of-thumb value.

• • The calculator returns a single recommended diameter. For mixed-metal joints, verify the rivet material against the sheet material so galvanic corrosion is controlled.
• • The shear check uses a single average load per rivet. A rivet pattern with uneven load sharing can size a few rivets too small.
• • The clearance hole is sized for a normal shop fit. Close-tolerance or aerospace joints use a smaller clearance and a different installation procedure.

The recommended diameter is rounded up to the next 0.5 mm so the result is a real shelf size.

According to UniPunch material specifications chart, annealed 302/304 stainless has a shear strength of 517 MPa, 6061-T6 aluminum has 207 MPa, and 5052-H32 aluminum has 138 MPa, which the calculator uses as allowable shear stress values for the strength check.

According to Wikipedia rivet article, a rivet should be placed in a hole ideally 4 to 6 thousandths of an inch larger in diameter than the rivet shank, which the calculator rounds to about 0.1 mm for small rivets and 0.2 mm for larger rivets.

When the riveted joint also bends under the applied load, the Bending Stress Calculator returns the bending stress in the same plate thickness and supports the same allowable stress check.