Patio planning

String Light Calculator

Estimate outdoor string-light cable, strands, bulbs, and attachment points for a rectangular patio.

Long side of the lighted area.

Short side of the lighted area.

Desired distance between parallel runs; also used as perimeter support spacing.

Extra cable for a gentle dip between supports.

Your estimate will appear here

Enter your project details and calculate for a practical planning estimate.

How this estimate works

  • Perimeter uses the rectangle’s perimeter. Zigzag uses full-length rows plus one cross-patio turn between each row. Grid adds full runs in both directions.
  • Rows are added until the chosen spacing covers the patio width (and both dimensions for a grid).
  • The straight-line cable total is increased by the selected swag percentage. Strand and bulb counts are rounded up so the installation is not short.

Before you begin

  • This is a planning estimate for a level rectangular area, not a structural or electrical design.
  • It does not include the power lead, extension cord, corner offsets, poles, trees, obstructions, or extra cable needed to route around them.
  • Actual drape depends on support height, cable weight, tension, wind exposure, and local code requirements; no live weather conditions are used.

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