How much helium does a balloon need?

A standard 11-inch latex balloon needs about 0.5 cubic feet of helium. A 16-inch latex needs about 1.0 cubic feet. An 18-inch foil balloon needs about 0.5 cubic feet. Larger balloons need exponentially more helium because volume increases with the cube of the diameter.

What size helium tank do I need for 50 balloons?

For 50 standard 11-inch latex balloons, you need approximately 25 cubic feet of helium (plus 10% wastage). A large disposable tank (28 cubic feet) would be sufficient. For a mix of latex and foil, calculate each type separately.

How long do helium balloons float?

Standard 11-inch latex balloons float for 8-12 hours. Larger latex balloons float longer (12-24 hours). Foil balloons can stay inflated for 3-5 days. Using Hi-Float sealant can extend latex balloon float time to 24+ hours.

Is it cheaper to buy or hire a helium tank?

For fewer than 30 balloons, a small disposable tank is cheapest. For 30-60 balloons, a large disposable or small hire tank offers best value. Over 60 balloons, hiring a large refillable tank is most economical. Factor in the deposit for hire tanks.

Helium Tank Size Calculator

Calculate the right helium tank size for your balloons with float time and cost estimates.

Latex Balloons

Balloon quantity or type

Foil Balloons

Balloon quantity or type

Latex Size

Standard or custom latex balloon size

Foil Size

Standard or custom foil balloon size

Tank Cost Override (optional)

Leave blank for typical pricing

How We Calculate This

This calculator estimates total helium needed based on balloon count, sizes and type, then recommends the most suitable tank.

Helium per balloon (defaults)

11-inch latex: 0.5 cu ft
18-inch foil: 0.5 cu ft
Larger sizes scale by the cube of the diameter ratio

Formula

Total helium = (latex count x helium per latex) + (foil count x helium per foil) x (1 + wastage%)

Frequently Asked Questions

Related Calculators

Balloon Calculator

Calculate how many balloons you need for your party venue, including latex, foil and helium options for any celebration. Free online calculator.

Bunting Calculator

Work out how many metres of bunting to buy for your party venue or garden based on the space you want to decorate. Free online calculator.

Streamer Calculator

Estimate how many rolls of streamers and crepe paper you need to decorate your party venue or celebration space. Free online calculator.

Table Decoration Calculator

Plan centrepieces, runners and table decorations for each table at your party or event. Get quantities right first time. Free calculator.

Confetti Calculator

Calculate how much confetti you need for your celebration, wedding send-off or party table scatter based on guest numbers. Free calculator.

Last updated: March 2026

All calculations are estimates. Adjust quantities based on your guests and event type.