Estimate lighted length before bulb count

Christmas Tree Light Calculator

Use tree height, width, shape, branch density, desired brightness, wrap style, and set length to estimate a planning range.

Planning result

133.7–170.1 ft of lighted length

Plan about 401–510 bulbs at 4-inch spacing, or roughly 6 sets at 33 ft each.

Tree: 7.5 ft × 4.5 ft · full
Density: Average branches · balanced light look
Wrap: Outer branches
Extra allowance: Keep one spare compatible set only after checking model and connection rules

Verify before acting

Bulb-count math depends on actual lighted length and spacing; total cord length can be longer.
Do not treat set count as approval to connect the sets end-to-end. Follow the exact product label and instructions.

01

Enter the room, route, or product claim

Inputs remain visible so you can challenge the assumptions.

02

Use the range as a shortlist

The result narrows questions; it does not certify a product or room.

03

Measure and verify

Check the real space, documentation, safety limits, and seller before purchase or installation.