Christmas Tree Calculator: Find Your Tree Size, Lights & Baubles

Realistic decorated Christmas tree styled with warm fairy lights in a living room

The free Christmas tree calculator from Christmas World — find the right tree height for your ceiling, then get the lights, baubles and skirt sizes to match, using the same formulas from our Australian decorating guides.

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How it works

Pick your ceiling height and the look you love, and the calculator sizes the tree and everything on it: total bulbs of lights and the strand count, baubles by pack, and the tree skirt diameter your stand needs. (Full guide content, FAQs and styling tips to come — content team.)

Christmas Tree Calculator

Two quick questions — the right tree size for your room, plus the lights, baubles and skirt to dress it.

Measure floor to ceiling where the tree will stand — including any carpet underlay.
The look you want

Your tree plan

7.5 ft tree (2.3 m)

Fits under a 2.7 m ceiling with 30 cm to spare for the topper

Tree size7.5 ft (2.3 m)
Lights750 bulbs
Baubles~190 baubles
Tree skirt~140 cm diameter

Allow 30 cm between the topper and the ceiling.

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Christmas lights Baubles Tree skirts & collars Tree toppers

The formulas behind the calculator
  • Tree size: your ceiling height minus 30 cm of clearance for the topper and breathing room, then the closest standard tree size below that. Every tree includes its own stand.
  • Lights: tree height (ft) × 75, 100, 150 or 200 bulbs per foot — sparse, classic, rich or showstopper. Cluster lights need about half the fairy count.
  • Baubles: roughly 15–45 per foot of height depending on the look, rounded to pack sizes.
  • Tree skirt: a skirt should be about two-thirds of the tree’s width plus a hand of margin — around 60% of height + 15 cm.

Estimates only, shown with the arithmetic — dress your tree to your own taste. Full advice in our guides.