Work out origami paper size instantly with clear inputs, formula shown and shareable results.
Each classic model folds down to a roughly fixed fraction of the starting square, so the sheet size is the finished size multiplied by that model's shrink ratio. Origami sheets come in fixed sizes, so working backwards from the finished model is the only way to avoid a crane half the size you wanted.
Sheet size
sheet side = desired finished size x model shrink ratio
Diagonal
diagonal = side x square root of 2
sheet side = desired finished size x model shrink ratio. Each classic model folds down to a roughly fixed fraction of the starting square, so the sheet size is the finished size multiplied by that model's shrink ratio.
Origami sheets come in fixed sizes, so working backwards from the finished model is the only way to avoid a crane half the size you wanted.
Enter desired finished size, model. The defaults shown are a realistic worked example — swap in your own figures to get a result you can use.