How many balloons per person at a party?

For a casual party, plan 1-2 balloons per guest. For moderate decoration, 3 per guest works well. For a full balloon decor theme, you may need 5 or more per guest. These include table balloons, floating balloons, and entrance decorations.

How long do helium balloons last?

Standard 28cm latex balloons last 8-12 hours with helium. Larger balloons last longer, and foil balloons can stay inflated for days. For a party, inflate helium balloons as close to the event start as possible.

Should I buy extra balloons?

Yes, always buy 10-15% more than you need. Balloons can pop during inflation, tie badly, or deflate early. Having spares means you can replace any that fail without a last-minute dash to the shops.

What is the best balloon size for parties?

The standard 28cm (11-inch) balloon is the most versatile and affordable. Use a mix of sizes for visual interest — combine 28cm with some larger 40cm balloons for a professional look.

PartyCalcs

Balloon Calculator — How Many Balloons for a Party

Calculate how many balloons you need for your party venue based on guest numbers and decoration style.

Number of Guests

Total number of people attending

Decoration StyleType or quantity of decorations

Balloon SizeStandard or custom balloon diameter

Balloons per Pack

Balloon quantity or type

Price per Pack (optional)

Unit price for cost estimation

Include spare balloons

Extra balloons for popping and inflation failures

How We Calculate This

This calculator estimates balloon quantities based on guest count and decoration style.

The formula

Total balloons = guests x balloons per guest + spares

The rate varies by decoration style: 1.5 per guest for casual, 3 for moderate, and 5 for full balloon decor. A 15% spare allowance is added by default to cover popping and inflation failures.

Frequently Asked Questions

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Last updated: February 2026

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