Use the calculation carefully
For an exact square, diagonal length is side multiplied by the square root of2. A25-inch square has a mathematical diagonal of about35.36 in before considering hems, fold thickness or how it is arranged.
Keep usable ends unknown
A knot or folded band consumes fabric. We have not tested a tying method on the named items or verified how much remains at each end. Do not treat the diagonal as a promise of a particular look.
Compare the original shape
A narrow rectangle and a diagonally folded square can share one long dimension while having very different widths and bulk. Keep both original measurements in the purchase record.
Before you decide
- Start with the actual side length
- Do not promise knot reach
- Keep the original shape visible
Sources & scope
Checked November 4, 2026. Official textile guidance, brand and retailer sources support the specific statements. Dated displayed prices are not final checkout quotes, wear-performance rankings or recall clearance. This shopping reference does not replace the product label or item-specific care directions or qualified textile-care advice.
Keep reading
Scarf, shawl or wrap: begin with dimensions ↗
Convert inches and cm without changing the garment ↗
Check whether fringe is inside or outside the stated length ↗