What speed does Google Maps use to estimate walking time?

SHORT ANSWER

About three miles an hour, but it varies depending on terrain.

FULL STORY

As far as we can tell, Google Maps doesn’t publish its method of working out your walking speed.

We asked, but they haven’t replied yet – so we did some tests.

On a fairly flat piece of Surrey countryside (with pavements) Google reckons it should take you an hour to walk three miles. Our maths department tells us that’s three miles per hour.

So far so good, but what if you go up or down a hill?

Posting online, one Google employee said Google Maps accounts for this sort of thing.

To check, we chose Edinburgh’s famous Royal Mile, which slopes from Edinburgh Castle down to the Palace of Holyroodhouse.

And Google Maps turns out to be pretty clever: It says it should take you 17 minutes to walk down the Mile – but 21 to walk up.

Taking a more extreme example, it reckons walking up Ben Nevis (Britain’s tallest mountain) takes two hours and 42 minutes, while descending takes an hour and 57 minutes.

But here Google might’ve got too big for its digital boots, as Ben-Nevis.com says it takes three-and-a-half to four hours – or even longer – just to reach the top.