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Central AC vs mini-split, side by side.
One house, two ways to cool it. Flip between systems, click rooms to move the family around, crank the outdoor heat — and watch the airflow, the duct losses, the comfort spread, and the running cost react in real time. Built for homeowners weighing a quote, and for pros who'd rather show than tell.
The 10-year math.
Sticker price is half the story — the other half arrives monthly, on the electric bill. Describe the house and see a typical installed-cost range plus ten years of cooling energy for each system, stacked into one honest bar.
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Head to head.
Nine categories, no fence-sitting — except where the honest answer really is "it depends."
Upfront cost
With healthy ducts already in the walls, swapping a central unit is usually cheaper. No ducts? Adding them often costs more than a multi-zone mini-split install.
Energy bills
Higher efficiency ratings, zero duct losses, and inverter compressors that glide instead of slamming on and off. The bill gap widens every hot month.
Room-by-room control
Every head is its own thermostat. Cool the office at 71° while the guest room sits off — central's single thermostat can't do either.
Whole-home evenness
One system pushing air to every room keeps an occupied whole house within a tight band — and recovers faster after a door's been open all afternoon.
Looks
Registers are nearly invisible; the equipment lives in the attic. Wall heads are tidy, but they're furniture you can't move.
Air filtration
One return pulling the whole house through a real media filter beats washable screens in each head — a big deal for allergies and dust.
Indoor noise
Heads whisper at a hum most people stop noticing; there's no whoosh of register air or blower spin-up at 2 AM.
Heating too
Nearly every mini-split is a heat pump, and cold-climate models hold capacity well below freezing — one install can retire both the AC and the furnace.
Homes without ducts
Older houses, additions, garages, sunrooms: a small wall penetration and a line set beat tearing open ceilings for new ductwork, every time.
Which one fits your home?
Five quick questions. No email, no login — just a straight answer and the reasons behind it.
1.Does the home already have ductwork in decent shape?
2.Whole house evenly, or specific rooms?
3.What matters most?
4.Any rooms that never feel right — too hot upstairs, freezing office?
5.Should this system heat in winter too?
A pointer, not a quote — a good local installer will pressure-check it against the actual house.
Fair questions.
The ones that come up at every kitchen-table estimate.
Can mini-splits really cool a whole house?
Yes. Multi-zone systems run several indoor heads off one outdoor unit, and ducted mini-split air handlers can quietly cover open-plan areas from a closet or soffit. Whole-home installs are routine in houses that never had ducts — the trade-off is more visible indoor equipment and a higher upfront price as the zone count climbs.
Do mini-splits heat in winter too?
Almost all of them — they're heat pumps. Modern cold-climate models keep meaningful heating capacity well below 0°F, which is why a mini-split quote often turns into a replace-the-furnace-too conversation. Run the numbers on both seasons before comparing prices.
Why is one room always hot with central AC?
Central AC takes orders from a single thermostat in one hallway. Rooms at the end of long duct runs, over garages, or behind big west-facing windows receive less effective airflow, so they settle a few degrees warmer than wherever the thermostat lives. Leaky attic ducts — commonly 20–30% loss — widen the gap. The animation up top shows exactly this: watch the kitchen.
What do SEER2 numbers actually mean?
SEER2 is cooling delivered per unit of electricity over a season — bigger is better, and the jump from 14 to 21 is roughly a third off the cooling portion of the bill. We built a separate SEER savings calculator that turns the rating gap into dollars for your exact rate and runtime.
How the simulation works. The house models heat creeping in from outside, body heat from whoever's home, per-room airflow differences, attic duct losses that grow with outdoor temperature, a single-sensor thermostat for central, and inverter modulation per head for the mini-split. Power draw assumes a 3-ton SEER2-15 central system against a four-zone SEER2-21 mini-split at $0.16/kWh. Cost ranges are national ballparks for comparison — real quotes vary by market, house, and installer, so treat every dollar figure here as a conversation starter, not a bid.