How We Test

1. What this site is — and what it isn't

CoolCompair is a price-comparison and shortlist-building site for portable air conditioners and fans. We are not a hands-on test laboratory; we don't run BTU-output verification in a calorimetric chamber, and we don't take blower-wheel acoustic measurements. What we do is collect, normalise and compare the data that already exists — manufacturer spec sheets, energy labels, retailer pricing, aggregated buyer ratings — and turn it into a shortlist a real shopper can act on in five minutes. We say so plainly because the alternative is dressing up reviewer scores with adjectives that imply hands-on testing we haven't done. We won't.

2. Where the numbers come from

Every figure on a product page on this site is one of three kinds:

• Manufacturer-published spec. BTU rating, coverage area, dB, energy label, weight, dimensions. We pull these from the official product page and corroborate against a second retailer listing where possible. If the two disagree, we mark the figure with a small "disputed spec" badge and use the lower claim.
• Retailer-published price. Re-fetched at least once a day. We look at the buy-box price, not the strike-through "was" price, and we never report a basket-discount price as if it were the shelf price. Pages older than 48 hours show a "Price may have changed" badge until they refresh.
• Aggregated buyer signal. Amazon star rating and total review count, scraped nightly per locale. We do not attempt to score a product on individual reviews — too noisy, too easily gamed.

3. The score

Each product receives a single 0–10 score, computed as a weighted average of five sub-scores:

• Cooling / airflow (30%). BTU rating for ACs (with a floor: anything below 7,000 BTU is capped at 6/10 in this dimension). For fans, claimed CFM or m³/h.
• Energy efficiency (20%). EU/UK energy label class. A+++ → 10/10, A++ → 9/10, and so on down to G → 2/10. We surface a warning on any portable AC sold in the EU/UK without a label, since MEPS rules require one.
• Noise (15%). Manufacturer-published dB at the lowest and highest setting. Below 50 dB at minimum speed is essentially "bedroom safe" and scores 8+; above 65 dB at minimum speed scores 4 or below.
• Build & longevity (15%). Warranty length, spare-parts availability, brand-level reliability data from Which?, Consumer Reports, and the aggregated Amazon-rating signal.
• Value (20%). Score above divided by current best retailer price, normalised against the category median. A good product at a bad price will score lower than the same product on sale.

These weights are chosen for the typical shopper buying a portable AC or fan for a 15–30 m² UK / US bedroom or living room. They are not appropriate for commercial cooling, marine cabins, or grow-tent applications — for those, the best-fit answer is rarely on this site.

4. How we keep prices honest

The price on each product page is fetched from the retailer's public product page on a daily refresh cycle. Where a retailer's anti-bot blocks us — Amazon will sometimes show a CAPTCHA challenge page rather than the product page — we fall back to the most recent price we successfully fetched, and we mark the listing "Price last verified N hours ago" so a reader can see how stale the figure is. We never invent a price. We never round a price to make a deal look bigger than it is.

5. How we handle dead / out-of-stock listings

Every retailer URL in our catalogue is health-checked nightly. If a URL returns a 404, 410, or DNS failure, we mark it as a dead link and de-prioritise it in the listings. If you click a "See at retailer" button for a product whose URL has gone dead, we route you to the cheapest working retailer offer for the same product instead of dropping you on the retailer's 404 page.

6. The "What buyers say" paragraph

Below the spec table on every product page is a short paragraph summarising what the aggregated rating and spec sheet tell us. It draws only on the verified Amazon star rating, the number of ratings, and the manufacturer's published specifications. No quotes are invented, no reviewer names are cited, and no anecdotes are fabricated. The paragraph is refreshed regularly and dated.

7. Locale handling

Products are sold in different specifications in different markets — a UK De'Longhi Pinguino is not the same SKU as the US one. Each locale has its own offer set, its own retailer mix, and its own aggregated Amazon rating. We don't cross-reference a product's UK rating into the US listing or vice versa.

8. What we don't test, and why we don't pretend to

We do not measure cooling output in a sealed chamber. We do not do long-term reliability testing (we don't run a dozen ACs for 18 months). We do not perform acoustic measurements. Sites that publish these tests well — Which?, Consumer Reports, RTINGS, the Wirecutter — do them properly, and we cite their findings rather than fake our own. If a product's real-world performance materially diverges from its spec sheet according to one of those sources, we surface that on the product page.

9. Corrections and challenges

If a manufacturer or shopper believes a figure on this site is wrong, email hello@coolcompair.com with the URL and the evidence. We respond within one trading day, correct verified errors, and log a correction note at the bottom of the affected page. See our Editorial Policy for the right-of-reply process.

10. When we update this methodology

We will publish material changes to this scoring rubric here, with a dated note explaining why. The current version was last reviewed in May 2026.