Calculate a practical sheet metal flat blank size from finished dimensions, bend allowance or bend deduction, with optional trimming and cutting allowances.
Enter the allowance or deduction from your bend calculation, tooling data or shop standard.
These allowances are optional practical additions for trimming, cutting or setup. Set them to zero when they are already included in your shop dimensions.
Enter the dimensions and calculate.
What does this calculator determine? It estimates the flat sheet blank dimensions required before bending a simple sheet metal part.
What is bend allowance? Bend allowance represents the material length consumed through the bend and is normally measured along the neutral axis.
What is bend deduction? Bend deduction is a shop-friendly method for determining the flat blank from finished flange dimensions.
Why does thickness matter? Material thickness affects the neutral-axis position, bend radius and therefore the developed flat length.
Can this calculate complex sheet metal parts? This calculator is intended for simple dimensions with a known total bend allowance or bend deduction. Complex multi-bend profiles should be developed using dedicated sheet-metal CAD or validated bend tables.
Should kerf always be added? No. Only add a cutting allowance when your manufacturing process requires it and it is not already included in the supplied dimensions.