UK air conditioning, made simple
What size air conditioner do I need?
Free, accurate UK calculators to size a unit, estimate running costs and compare efficiency — backed by buying guides and honest top picks. No sign-up, no jargon.
- ✓ Based on current Ofgem rates
- ✓ Built for UK homes
- ✓ Completely free
Free calculators
Three tools to choose with confidence
Everything you need to pick the right air conditioner and understand exactly what it will cost to run.
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BTU calculator
Enter your room dimensions and heat sources to get a recommended BTU output.
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Running cost calculator
Estimate annual and hourly running costs based on unit size and usage hours.
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Efficiency calculator
Compare SCOP and EER ratings to find the most efficient unit for your budget.
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Buying guides
Plain-English advice for UK homes
Long-form guides covering sizing, running costs and what to check before you buy — no fluff, no hard sell.
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Air conditioning installation cost UK (2026 guide)
Typical 2026 UK costs for installing single-split and multi-split air conditioning, what changes the quote and what a proper installation should include.
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Portable air conditioner window kits and venting guide
Choose and fit a portable air conditioner window kit for UK casement, sash, sliding and tilt-and-turn windows, with practical sealing and hose advice.
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Air cooler vs air conditioner: which works in the UK?
Compare evaporative air coolers, fans and portable air conditioners for cooling power, humidity, electricity use, noise and UK room conditions.
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Top picks
Best portable air conditioners UK (2026)
Ranked by BTU output, room coverage, efficiency and noise — with buying tips and links to our free size and running-cost calculators.
Preview — we're still finalising our real picks. The guide covers what to look for so you can assess any unit yourself in the meantime. Check back soon for live recommendations.
Browse all top picks →Common questions
Quick answers before you buy
- How many BTU do I need for a typical UK bedroom?
- Most UK bedrooms (around 10–15 m²) need 5,000–8,000 BTU. South-facing rooms or rooms with large windows may need more. Use the BTU calculator for a personalised figure.
- How much does it cost to run an air conditioner in the UK?
- A typical 9,000 BTU portable unit running for 8 hours a day in summer costs roughly £1–£1.50 per day at current UK electricity rates. Try the running cost calculator for your own figures.