BendPro

Conduit Bending Math, Off Your Sticker and Onto Your Phone

Every electrician carries the same handful of numbers in their head: 30° offset multiplier 2, 45° multiplier 1.4, 22.5° multiplier 2.6. The shrink per inch of offset depth. The take-up for a 1/2" Klein. The gain on a 90° bend. They're stamped on the bender shoe, scrawled on a sticker, written inside a hardhat. BendPro is that sticker, with the multiplication done for you, the deductions baked in, and a diagram that shows where the marks go.

Offsets Without the Mental Math

The offset is the bend you make ten times a day — around a junction box, under a beam, over a strap. Depth in, angle picked, distance between bends and shrink out. The shrink is the number nobody wants to calculate manually because it ruins the whole pull when you forget it: a 6" offset at 30° shrinks the conduit by about 1-1/2" depending on bender, so the mark you make for the start of the bend has to be 1-1/2" past where you actually want the offset to land. BendPro handles it. The diagram shows the mark, the bend, the offset, the next mark.

Saddles Around Obstructions

A 3-point saddle is the bend you make around a single pipe or beam. A 4-point saddle is the bend around a wider obstruction where the center has to stay flat. The math for both is the same — center angle, outer angles, mark spacing, total shrink — and the math is genuinely annoying without a reference. BendPro draws the obstruction at scale, shows you where each mark falls along the conduit, and labels every angle so you can match it on the bender.

Stub-Ups With Real Bender Deductions

A 90° stub-up is rise minus take-up. Take-up is different for every bender, every conduit size, every material. Klein, Greenlee, Ideal, and Gardner Bender deduction tables are built in. Pick your bender brand, pick your conduit size, enter your stub height, and BendPro returns the mark from the end of the conduit. If your bender isn't listed, Premium lets you save a custom profile so the deduction is right next time.

Rolling Offsets and Kicks

Rolling offsets are the bends that send a conduit run horizontally AND vertically in the same pair of bends — common when you're chasing a structural member or threading through a congested ceiling. BendPro returns the roll angle, the true offset, and the conduit travel, with the geometry drawn out so you can sanity-check the orientation before you bend. Kicks (a 90° + a small offset at the same point) are handled with kick height and distance — angle and travel out.

NEC Chapter 9 Wire Fill

Wire fill calculations are the other number you forget right before you need it. NEC Chapter 9 sets the maximum percentage of conduit cross-section that conductors can occupy: 53% for one conductor, 31% for two, 40% for three or more. EMT, IMC, Rigid, and PVC each have their own internal area per trade size. BendPro lets you add conductors by type (THHN/THWN, XHHW) and gauge, and it shows the running fill percentage with the NEC limit clearly marked. Over-fill turns red — catch it at the calculator instead of the inspector.

Privacy and Offline Use

Every calculation, every favorite, every saved bend lives on your device. No account, no cloud sync, no analytics on your job data. The app works completely offline — basements, parking garages, mechanical rooms. The free tier includes ads; Premium removes them.

For Estimation — Verify Against the Stamp

BendPro is a calculator, not a license to skip the deduction on the bender. Manufacturing tolerances, conduit wall thickness variation, and even the shoe wear on a well-used bender can shift take-up by 1/16" or more. Every result screen reminds you: verify all measurements against the deduction stamped on your bender shoe before bending. For estimation only.