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Both calculators run independently β€” change the inputs on either side to compare results.

Sewing

Buttonhole Spacing Calculator

Calculate the center-to-center distance between buttonholes on a placket for evenly spaced results. Use it whenever adding buttons to a shirt, cardigan, blouse, jacket, or any faced opening.

Fill in the required fields to see your result.
Sewing

Seam Allowance Calculator

Calculate the total cut fabric area needed when adding seam allowances to a target finished size. Use it when drafting patterns, adjusting existing patterns, or estimating fabric for projects where the seam allowance reduces the finished dimensions.

Fill in the required fields to see your result.

Key differences

Buttonhole Spacing CalculatorSeam Allowance Calculator
CategorySewingSewing
Inputs required43
ResultSpacing Between Buttonholes (inches)Total Fabric Area (square inches)
What it doesCalculate the center-to-center distance between buttonholes on a placket for evenly spaced results. Use it whenever adding buttons to a shirt, cardigan, blouse, jacket, or any faced opening.Calculate the total cut fabric area needed when adding seam allowances to a target finished size. Use it when drafting patterns, adjusting existing patterns, or estimating fabric for projects where the seam allowance reduces the finished dimensions.