Where do I lengthen or shorten a pattern?

Patterns have printed lengthen/shorten lines — horizontal double lines across the pattern piece. Cut along this line to spread (lengthen) or overlap (shorten). Never adjust at the hem line, as this changes the hem shape.

What if there is no adjustment line?

Draw your own adjustment line perpendicular to the grainline, midway between the waist and the hem (for skirts) or between the armhole and waist (for bodices). Keep it in a straight section, not across darts or shaping.

How do I measure my length?

For bodice length, measure from the shoulder point (where shoulder meets neck) over the bust to the natural waist. For skirt length, measure from the waist to the desired hemline. Compare with the pattern measurement.

SewCalcs

Length Adjustment Calculator — Lengthen or Shorten Patterns

Calculate how much to lengthen or shorten pattern pieces at the correct adjustment lines.

Your Desired Length

Measured on your body

Pattern Length

Measured on the pattern piece

Pattern Piece

How We Calculate This

The adjustment is simply the difference between your desired length and the pattern length.

The formula

Adjustment = Desired length − Pattern length

Positive = lengthen (spread pattern). Negative = shorten (overlap pattern).

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always verify quantities before cutting or purchasing fabric.