There are already a few excellent websites, such as www.traveljungle.co.uk and www.skyscanner.net, that compare online air fares. Type in a destination and your dates, and they’ll sift through dozens of other sites to find the cheapest, delving deep into computer reservations systems to get live prices in a process known as “screen-scraping”.

Now this technology is being aimed at the hotel market, allowing independent travellers to scour the net for the cheapest rates in seconds: a process that would previously have taken hours. And while air fares on the web tend to differ by a few pounds, the price of discounted hotel rooms can vary by more than 50%.

Let’s take an example. Suppose you are inspired by the news that Ryanair has just begun flying from Stansted to Seville. You might snap up a couple of cheap flights, then decide to look for a hotel. The simplest way to do this is by clicking through from www.ryanair.com to www.ryanairhotels.com. Let’s say that, having saved on your flights, you decide to treat yourself to a stay at the five-star Alfonso XIII, a 1920s palace in the city centre. The price for two nights on the first weekend in June? A princely £815, according to Ryanairhotels.com.

A little more than you planned to spend? Indeed, but you’re not the type to be easily deterred. So you start searching the internet for a better rate, quickly discovering that there are scores — maybe hundreds — of websites offering to book you a room at the Alfonso. Trawling through them will take all night.

Instead, you go to a price-comparison website called Kelkoo (www.kelkoo.co.uk) and type in the name of the hotel and your dates. In less time than it takes to sharpen a pencil, Kelkoo has found a lower price for the same two nights. And not just a bit lower — when we conducted this particular experiment, it directed us to Opodo (www.opodo.co.uk), which quoted £514.

This is getting interesting, isn’t it? But there’s a small caveat. There isn’t just one super-duper website that compares online hotel rates, there are at least half a dozen — and because they each trawl a different set of sites, they tend to return different results. Sometimes wildly different. To find out which is best, we put them to the test.

()The experiment

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