FREE · CALCULATORS & CONVERTERS
Bend Allowance Calculator.
Calculate bend allowance, bend deduction and flat length from the angle, radius, thickness and K factor.
K is limited to 0–0.5. The angle is greater than 0 and below 180 degrees. Flat length uses the outside legs. Local arithmetic only. This is a quantity or geometry estimate, not a code check and not a substitute for a licensed professional.
- Bend allowance
- 0.004178 m
- Bend deduction
- 0.003822 m
- Flat length
- 0.096178 m
Bend allowance = angle in radians × (inside radius + K × thickness). Bend deduction = 2 × (radius + thickness) × tan(angle / 2) − bend allowance. Flat length = outside leg 1 + outside leg 2 − bend deduction.
How to use Bend Allowance Calculator
Enter the inside radius, thickness, bend angle and the two outside legs. K is often near 0.33 and can be edited.
How it works
Calculate bend allowance, bend deduction and flat length from the angle, radius, thickness and K factor. K is limited to 0–0.5. The angle is greater than 0 and below 180 degrees. Flat length uses the outside legs. Local arithmetic only. This is a quantity or geometry estimate, not a code check and not a substitute for a licensed professional.
Example
A 90° bend, 2 mm radius, 2 mm sheet and K = 0.33.
Questions about Bend Allowance Calculator
Is Bend Allowance Calculator free, and do I need an account?
Yes. This tool is free to use in your browser without an account. Processing takes place on your device.
What are the limits and what should I check?
K is limited to 0–0.5. The angle is greater than 0 and below 180 degrees. Flat length uses the outside legs. Local arithmetic only. This is a quantity or geometry estimate, not a code check and not a substitute for a licensed professional. Review the result before using it in your work.
Is my input sent to a server?
Your input is processed in your browser and is not uploaded by this tool. Files and pasted text are cleared when the page is refreshed. Normal website requests are still required to load the page and its libraries. Read the privacy explanation.