Many travellers find the sheer volume of online booking tools to be overwhelming. So this is the third in a month-long series that highlights a handful of websites that will change the travel game in 2013. Previous posts were on GetGoing and Flightfox.

Unique premise
Lots of metasearch websites, including Kayak and Skyscanner, search for aeroplane tickets from multiple sources, sorting the results by cheapest first. Yet the most affordable fare might not be the most valuable one if you take into account the miles and related bonuses you could earn by flying a different airline.

Launched in November 2011, the US-headquartered metasearch site Superfly lists airfares in order of “net value” – basically ­­the cost of the ticket minus the cash value of the miles you could earn and someday redeem for rewards, such as free flights, seat upgrades and status upgrades.

The website covers more than 100 loyalty programmes run by airlines, credit cards, hotel chains, train lines and car hire companies worldwide, and, after you sign up, takes into account your current mileage balances, so each user will see different search results based on their differing travel histories and memberships.

Additionally, to make its calculations, Superfly doesn’t just count the number of miles a flight crosses, but also accounts for the weird quirks of frequent flyer programmes.

For instance, people who have status in a major loyalty programme typically benefit from a greater redemption value on the miles they collect  – a factor, or “multiplier”, that Superfly considers when determining net value. Similarly, if you’re buying a first or business class seat, Superfly will account for each airline’s mileage bonus for that type of ticket. That said, you only see potential reward opportunities for programmes you belong to, and in all of its calculations, the site assumes you will fly often enough to eventually earn rewards.

Test case
Say you’re searching for a direct flight in May between Chicago and London, and Superfly finds tickets that are the same price, $934, on British Airways and United – two programs where you have the same mileage balance and no status level. While each flight is the same number of miles and costs the same, one could prove more rewarding if it were on an airline that makes it easier to redeem the miles for a free flight, a seat upgrade or a status upgrade.

On a recent test search for this ticket, Superfly estimated that United’s miles were worth $118 in eventual rewards, reducing the United ticket to a net value of $816. Meanwhile it predicted that British Airways’ miles would be worth only $59 in rewards, creating a net value of $875.

On this route, the British Airways ticket isn’t as valuable because the carrier requires more miles than United does to reach a status level that leads to cash-equivalent benefits.

Flaws that need fixing
Superfly doesn’t let you see any airfares until you create an account, so a user can’t sample the site until he or she has already invested several minutes in signing up and recording which loyalty programmes they belong to.

In November 2012, Superfly added an experimental feature to speed up the process of plugging in frequent flyer information. Rather than enter your membership numbers manually, a traveller can authorise Superfly to scan his or her Gmail inbox for messages that contain frequent flyer information. The site then extracts point balances from those emails daily.

The e-mail scanning service doesn’t yet work with Microsoft Outlook, Hotmail or other e-mail services, though the company says it will launch compatibility with Yahoo! Mail and AOL Mail on 15 March.

While you can manually input membership information for up to 100 programmes, the site’s email-based system automatically recognises frequent flyer information for only 11 brands: Air Berlin, Alitalia, American, American Express, British Airways, Delta, Indigo Airlines, Hilton, Southwest, Starwood and United, thought the start-up says more brands will be added this year.

In a drawback, Superfly doesn't show you the potential net value of tickets on airlines or alliances whose mileage programmes you haven't yet joined. That’s a problem if you’ll be travelling on new routes often and will likely come across many airlines you haven't flown. After all, it would be impractical to join all of those programmes and enter the membership numbers into Superfly merely to see which one would be the best to invest time and money in. So the site is useful primarily for travellers who plan to concentrate their mileage-building effort, flying repeatedly on either one airline or on a limited number of airlines.

Sean O’Neill is the travel tech columnist for BBC Travel