How is conduit offset length calculated?

For a symmetric offset, the sloped section is estimated from offset depth and bend angle, then the two identical legs are combined.

Does this calculate shrink or take-up?

No. Actual fabrication marks depend on the bender, conduit size and selected bending method.

Can I change the bend angle?

Yes. A different angle changes the developed length.

Conduit offset geometry

Conduit Offset Length Calculator

Estimate developed conduit length for a symmetric two-bend offset while keeping bend angle and straight-leg allowances explicit.

Offset inputs

Offset depth

Bend angle

Straight-leg allowance per sideOptional straight distance outside the sloped portion.

Number of identical offsets

Length unit

This is geometric planning only. Bender take-up, gain, marks, shoe geometry and actual fabrication practice vary by tool and conduit system.

Enter offset depth and bend angle.

Offset result

Estimated developed length

—

—Sloped section

—Length / offset

—Total quantity

—Angle

—

Offset geometry

For two equal bends, the sloped centerline length on each side is approximated as offset depth divided by sin(angle). Two identical sloped sections are then combined with any specified straight-leg allowances.

Sloped section = offset depth ÷ sin(angle)
Per-offset developed length ≈ 2 × sloped section + 2 × leg allowance

Worked example

A 150 mm offset using 30° bends has a geometric sloped section of about 300 mm per side. With 100 mm straight allowance per side, the estimated developed length is 800 mm per offset.

Why actual bends can differ

Field and shop bending methods can introduce shrink, gain and take-up effects. The geometric result should therefore be treated as a planning baseline rather than a cut-marking instruction.

Frequently Asked Questions

Can the bend angle be 90°?

The mathematical model becomes unsuitable for the intended offset interpretation as the angle approaches 90°. Keep the angle below 90°.

Can the offset depth be zero?

No useful offset exists at zero depth, so this calculator requires a positive depth.