London house prices per square foot, by postcode:

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Questions, answers and excuses:

Where do these numbers come from?

We've read the internal floor area from floorplans for over 18,000 properties for sale in London*. From the properties for sale in each postcode we calculate the median asking price per square foot of internal floor area.

Where does all your travel time data come from?

Public transport times come from Transport for London's Journey Planner tool. We've used mid-week, peak-time travel time.

We include: buses, the Underground, the Overground, trams, walking (if the quickest way), proper trains.

We don't include: cycling or boats.