Helium Tank Sizes & Balloon Count Guide

Q: How many balloons does a helium tank fill?

Exact counts depend on tank size, pressure, balloon size, and how full you inflate. As a rough guide, a 40 cubic foot tank fills about 80 to 85 standard 11 inch balloons, a 60 cubic foot tank fills about 120 to 125, and an 80 cubic foot tank fills about 160 to 170.

Q: What size helium tank do I need for 100 balloons?

For around 100 standard 11 inch balloons, a 60 cubic foot tank is usually a comfortable choice. A 40 cubic foot tank may come up short once you account for waste and imperfect fills.

Q: Can I refill a disposable helium tank?

Disposable party helium cylinders are not designed to be refilled. Most suppliers will refuse to refill them for safety and liability reasons.

Last updated: May 9, 2026

Need to know what size helium tank fills 30, 50, 100, 200, or 500 balloons? This guide compares common helium tank sizes, approximate balloon counts, and which tank size usually fits each event.

The estimates below use a standard 11" latex balloon at about 0.48 ft³ of helium per balloon. Real results vary with balloon size, fill level, regulator, temperature, balloon quality, and waste. Always confirm expected counts with your supplier.

Find a helium supplier → How to rent a helium tank Disposable vs refillable tanks

Quick answer: what size helium tank do I need?

30 balloons: around a 14.9–20 ft³ tank.
50 balloons: usually a 40 ft³ tank, or a 20 ft³ tank if you keep fills smaller.
100 balloons: usually a 60 ft³ tank.
150 balloons: usually an 80 ft³ tank.
250+ balloons: look at 125 ft³ or larger cylinders.

If the event matters, round up. Running out of helium halfway through decorating is the kind of avoidable misery humans keep inventing anyway.

Illustration showing small, medium, and large helium tank sizes with balloons above them.

Quick helium tank size cheat sheet

Small tanks

14.9–20 ft³
Roughly 30–40 standard 11" balloons. Best for small home parties, tiny events, or a few balloon bouquets.

Medium tanks

40–80 ft³
Roughly 80–165 standard 11" balloons. Best for birthdays, schools, churches, and medium event setups.

Large cylinders

125–250 ft³
Roughly 260–520 standard 11" balloons. Best for decorators, large events, arches, columns, and repeated use.

Not sure whether your tank can be refilled? Read the disposable vs refillable guide

Common helium tank sizes & approximate balloon counts

These are typical sizes you may see from welding gas suppliers, industrial gas suppliers, party rental companies, or disposable helium kits. Counts assume standard 11" latex balloons.

Tank size	Capacity	Approx. 11" balloons	Best fit	Notes
Small disposable kit	8–14.9 ft³	15–30	Tiny home parties	Usually not refillable.
14.9 ft³ kit	14.9 ft³	≈ 30	Small birthdays, baby showers	Convenient, but high cost per balloon.
20 ft³ portable	20 ft³	≈ 40	Small parties, simple bouquets	Sometimes rented for weekend use.
40 ft³	40 ft³	≈ 80–85	Kids parties, small school events	Good step up from party kits.
60 ft³	60 ft³	≈ 120–125	Medium events, 100-balloon plans	Good “safe middle” for many parties.
80 ft³	80 ft³	≈ 160–170	Larger parties, basic decor	Popular rental/decorator size.
125 ft³	125 ft³	≈ 260	Arches, columns, school events	Often better for frequent use.
150 ft³	150 ft³	≈ 310–315	Large rooms, fair booths	Heavy cylinder, usually carted.
200–250 ft³	200–250 ft³	≈ 415–520	Big installs, festivals, decorators	Industrial size. Do not freehand this beast.

Planning numbers, not guarantees. Add a 10–20% buffer if the event is important.

Tank size by event type

Small party

20–40 balloons
A 14.9–20 ft³ kit may work. If you want fewer surprises, ask about a small rental cylinder.

Medium event

75–150 balloons
A 40–80 ft³ tank usually makes more sense than disposable kits.

Large setup

200+ balloons
Start looking at 125 ft³ and larger cylinders, or consider hiring a balloon decorator.

Find helium near you → DIY vs balloon decorator

Helium needed by balloon size

If you are mixing balloon sizes, use these rough volumes to estimate total helium need.

Balloon size	Approx. helium	Common use
9" latex	~0.34 ft³	Small bouquets, filler balloons
11" latex	~0.48 ft³	Standard party balloons
12" latex	~0.52 ft³	Slightly larger party balloons
16" latex	~1.50 ft³	Large statement balloons

Foil and Mylar balloons vary by shape. Check the manufacturer’s packaging or product page when possible.

How to choose the right helium tank

1. Count the balloons

Include bouquets, centerpieces, arches, columns, ceiling balloons, and extras for popped or wasted balloons.

2. Match the tank

Use the chart above. For many parties, 40–60 ft³ is a practical range.

3. Add a buffer

Add 10–20% extra if the event matters. Under-buying is usually worse than having helium left over.

Refill vs exchange vs rental

Suppliers handle helium cylinders differently. Some refill your exact tank, some exchange it for a full one, and some rent tanks for short-term event use.

Refill: they fill the same tank you bring.
Exchange: you swap an empty cylinder for a full one.
Rental: you borrow a tank for a short period, often with a deposit.
Disposable kits: usually not refillable.

Ask: “Do you refill, exchange, or rent helium tanks, and what sizes are available today?”

What to ask before you drive

Call first. Helium availability changes, and not every supplier handles every tank size.

“Do you offer helium tank rental, exchange, or refill for the public?”
“What tank sizes do you have available right now?”
“How many 11–12" balloons does that size usually cover?”
“Do you include a balloon inflator nozzle or regulator?”
“What is the price, deposit, and rental period?”
“Do you accept customer-owned tanks?”

Open Helium Locator → DIY helium setup tips

Float time, temperature & waste

Balloon charts assume fairly ideal conditions. Real events are less polite.

Heat and sun shorten float time.
Cheap latex leaks helium faster.
Overfilling wastes helium and causes popping.
Underfilling saves helium but may look sad and float poorly.

For important events, inflate close to event time, use better balloons, and keep tanks and balloons away from heat.

Safety notes for any helium tank

Helium itself is inert, but compressed gas cylinders deserve respect.

Keep cylinders upright and secured.
Do not leave tanks in hot vehicles or direct sun.
Use proper caps, chains, straps, or carts when moving cylinders.
Do not try to refill disposable kits.
Do not inhale helium; it can displace oxygen.
Follow venue rules for schools, churches, hotels, and public buildings.

Next steps

Once you know your approximate balloon count, you can pick a tank size, call suppliers, and confirm availability.

Use the directory to find a helium refill, exchange, or rental supplier near you.
Read the helium tank rental guide if you need a short-term tank.
Check disposable vs refillable tanks if you are unsure what kind of tank you have.
Skim the helium accessories guide if you need regulators, straps, carts, or inflator parts.

Find helium near you → Helium 101 guide

Helium tank size FAQs

How many balloons does a helium tank fill?

It depends on the tank size and balloon size. As a rough guide, a 40 ft³ tank fills about 80–85 standard 11" balloons, a 60 ft³ tank fills about 120–125, and an 80 ft³ tank fills about 160–170.

What size helium tank do I need for 100 balloons?

For around 100 standard 11" balloons, a 60 ft³ tank is usually a safer choice than a 40 ft³ tank once you include waste and imperfect fills.

Can I refill a disposable helium tank?

Usually no. Disposable party helium tanks are not designed to be refilled, and most suppliers will refuse to fill them.

Is it better to rent or buy a helium tank?

For one event, renting usually makes more sense. Buying may only make sense if you regularly use helium and have a supplier willing to refill or exchange your cylinder.