For a classic look, use 100 lights per foot of tree height — a 7.5 ft full tree needs 750 lights, or 8 strands of 100 lights. Use the calculator below for your exact tree height, shape and brightness.
How to Use This Calculator
- Enter your tree height in feet.
- Choose Full or Slim shape and your brightness (density).
- Add roofline feet if you are also lighting the roof, then click Calculate.
Example: a 7.5 ft full tree at classic density needs 750 lights — 8 strands of 100 lights. If a field is empty, the calculator will ask you to fill it in instead of showing zero.
Christmas Tree Lights Calculator
Tree shape
Brightness (lights per foot)
Planning Your Christmas Lights
For a party table to go with your decorated tree, our Sandwich Party Calculator helps with buffet quantities.
Next, see what they cost to run with our Christmas Lights Electricity Cost Calculator.
Frequently Asked Questions
How many lights do I need per foot of Christmas tree?
Use 75 lights per foot for a minimal look, 100 for classic, 150 for bright and 200 for dazzling. A full tree needs the full amount; a slim tree needs about 20 percent fewer lights.
How many strands of 100 lights do I need?
Divide your total lights by 100 and round up. For example, 750 lights need 8 strands of 100 lights.
How many ornaments do I need for my tree?
About 15 ornaments per foot of tree height is a good guide — a 7.5 ft tree needs about 113 ornaments. Add more if you like a fuller look.