How many lights does a Christmas tree need?

A hundred LEDs per foot is the starting point. The type of set, the colour and where the socket is decide the rest.

LEDs by height

Tree	Even glow	Bright	Cluster set
4ft	400	600	480
5ft	500	800	480
6ft	600	1,000	720
7ft	700	1,200	960
8ft	800 to 1,000	1,500 to 2,000	960 x 2

Use the lower figure for a tree that will carry a lot of decorations, the higher one for a tree that is mostly lights. A slim or pencil tree takes about two-thirds of the number for its height.

String or cluster

A string set spaces its LEDs about 10cm apart along one cable; wrapped in a spiral it gives points of light through the tree. A cluster set hangs the LEDs on short stems off the main cable, so a metre of cable carries ten times as many bulbs and the effect is a solid band of light. Clusters need fewer bulbs for the same brightness and tangle less; strings reach deeper into the branches. On a dense tree a cluster set wrapped on the outside looks fuller; on a sparse tree a string set pushed in deep looks better.

Lit length and lead length

Two figures on every set. The lit length is how much cable carries bulbs: a 6ft tree needs about 20m of lit string to spiral from top to bottom. The lead length is the unlit run between the plug and the first LED, and it decides whether the set reaches the socket. A 5m lead crosses a room; a 1.5m lead does not. Check it before buying, not after.

Colour

Warm white reads as candlelight and suits green trees, red and gold decorations and brick. Cool or ice white is daylight and suits white, grey and flocked trees and silver decorations. Multi coloured is the family tree. Vintage gold is a darker amber. Mixing colour temperatures on one tree looks accidental; pick one.

Running cost

A 1,000-LED set draws about 6W. Six hours a night for the 42 days from mid-November to the end of December is about 1.5kWh, which at the October to December 2026 Ofgem price cap of 26.32p per kWh is roughly 40p for the whole season. A 2,000-LED set is about 80p. The cost of lighting a tree is not a reason to light it less.

Wrapping

Start at the trunk at the top and spiral down, pushing a loop into the tree every few turns so the inside lights as well as the tips. Plug the set in while you wrap so you can see the gaps. Put the lights on before any other decoration.

The tree lights and cluster lights sections list every set by bulb count, colour, lit length and lead length.