Balloon Arch Calculator
Estimate how many balloons you need to build a balloon arch or garland. Enter the finished length of the arch, the average balloon size you're using, and how densely you want it packed, and the calculator returns the total balloon count plus a colour-split breakdown.
Formula
Balloons ≈ ⌈ length (ft) × (12 ÷ balloon size in inches) × fullness ⌉
- Estimates how many inflated balloons it takes to cover a given arch length at the chosen fullness.
- Fullness multiplier: light ≈ 1.0, standard ≈ 1.3, full/organic ≈ 1.7 — fuller garlands use far more balloons.
- Mixing balloon sizes (e.g. 5", 11" and 16") gives the popular 'organic' look; use your average size here.
- Always inflate 10–15% extra to cover pops and gaps while building.
10 ft garland, 11" balloons, standard fullness, 4 colours
Inputs
- Arch / Garland Length: 10 ft
- Average Balloon Size: 11 in
- Fullness: 1.3
- Number of Colours: 4
Per foot ≈ 12 ÷ 11 = 1.09 balloons. Total ≈ 10 × 1.09 × 1.3 = 15 balloons. That's about 4 per colour, or roughly 17 including spares.
Frequently asked questions
How many balloons do I need for an arch?
As a rough guide, a standard-fullness garland uses around 15–20 11-inch balloons per metre (about 5–6 per foot for a full organic look). Enter your length and balloon size for a tailored figure.
Should I buy extra balloons?
Yes — always add 10–15% extra to cover balloons that pop while inflating or building, and to fill any gaps.
Does balloon size matter?
A lot. Larger balloons cover more length each, so you need fewer of them. Mixing sizes creates the popular organic, textured look.
What is the difference between an arch and a garland?
A garland is the cluster of balloons itself; an arch is a garland shaped into an arch over a frame or doorway. The balloon count is driven by length and fullness either way.