Cutting Length Formula & Calculator | BBS free course

CUTTING LENGTH FORMULA

Complete RCC Bar Bending & Cutting Length Guide with Calculator

1. Straight Bar

Formula

CL = L

Explanation

• Straight bars do not contain bends or hooks.
• No bend deduction is required.
• Cutting Length equals actual bar length.
• Used in slabs, beams, columns and footing reinforcement.

2. Bar with Two 90° Bends

Formula

CL = a + L + a − Bend Deduction

Bend Deduction = 2 × 2D

Explanation

• This bar contains two 90° bends.
• Each 90° bend causes deduction of 2D.
• Total bend deduction = 4D.
• Used in beam anchorage and column reinforcement.

3. Single 90° Bend Bar

Formula

CL = a + L − Bend Deduction

Bend Deduction = 1 × 2D

Explanation

• This bar contains one 90° bend.
• Deduction for one 90° bend = 2D.
• Generally used in slab anchorage and edge reinforcement.

4. Formula to Calculate Number of Bars

Condition	Formula
Including Start & End Bar	(Number of Bars) = Distance / Spacing + 1
Excluding End Bar	(Number of Bars) = Distance / Spacing
Excluding Start & End Bar	(Number of Bars) = Distance / Spacing − 1

Cutting Length Calculator

Select Bar Type Straight Bar Single 90° Bend Two 90° Bends Main Length L (mm) Side Length a (mm) Bar Diameter D (mm)

Calculation Result

Bend Deduction Table (IS 2502 Practice)

Bend Angle	Bend Deduction
45°	1D
90°	2D
135°	3D
180°	4D

Important Site Engineering Notes:

• Always measure cutting length along centerline of reinforcement.
• Bend deductions are subtracted because actual bent length becomes shorter.
• Use IS 2502 provisions for accurate BBS calculations.
• Hooks and bends should be prepared carefully to avoid steel wastage.
• Check reinforcement cover before preparing BBS.
• Maintain proper spacing and detailing during bar fixing.

Developed By

Mohan Dangi (Gold Medalist)