Pool Heater Size Calculator
Work out what size pool heater you need. Answer a few questions about your pool and how you use it, and the calculator returns a recommended heater output (in kW), then prices a unit to match.
Your pool heater size details
Bigger pools need more heater output to reach temperature in reasonable time.
A pool blanket dramatically cuts heat loss, so you can run a smaller heater.
Your estimate sits within the typical range.
An undersized heater never quite gets the pool warm and runs constantly. Size it to the pool and your climate, and always pair it with a blanket to keep the heat in.
Where the money goes
Estimated breakdown for your configuration
💰 Ways to save
- A pool blanket lets you run a smaller, cheaper heater and slashes running cost.
- Heat pumps cost more upfront than gas but far less to run for regular use.
or from $34/week over 5 years , indicative finance
How we estimate this
Most Australian pools need a 9kW to 18kW heater in 2026, costing roughly $3,000 to $12,000 supplied and installed depending on pool size and heater type. Bigger pools and year-round use need more output.
Pricing reviewed: October 2026.
Doing more than just pool heater size?
Build a combined estimate across every part of your project in one place.
Pricing reviewed October 2026. Indicative Australian costs, not a quote.
Understanding pool heater sizes in Australia
Most Australian pools need a 9kW to 18kW heater in 2026, costing roughly $3,000 to $12,000 supplied and installed depending on pool size and heater type. Bigger pools and year-round use need more output.
Size the heater to your pool volume, climate and how you use the pool, and always pair it with a blanket. A blanket cuts heat loss so much that you can run a smaller, cheaper heater.
Frequently asked questions
What size pool heater do I need?
Most pools suit a 9kW to 18kW heater, sized to pool volume, climate and use. A small plunge pool may need 9kW; a large pool for year-round swimming may need 25kW.
Does a pool blanket affect the heater size I need?
Yes, significantly. A blanket cuts heat loss so much that you can run a smaller, cheaper heater and save a lot on running cost. Without one, size the heater up.
Are you a pool / heating business?
Everyone on this page is working out what pool heater size costs because they are ready to hire. Put your business right beneath the calculator, in your state, so you are who they find. From $50/mo.