How London postcodes work on the map
· London
Outward codes, sectors, and full postcodes are three different sizes of London. Here is what each one means when you search WhichStreet.
A London postcode is not one place. It is three nested areas, and the map switches between them as you zoom.
The outward code
The first half, such as SW4 or E8, is the outward code. It covers a neighbourhood-sized patch of London. When the map is zoomed out, each dot is one outward code, so you can compare areas without the screen filling with thousands of points.
The sector
Add the first digit of the second half and you get a sector, such as SW4 9. A sector is smaller than the outward code and larger than a single street. It is useful when two sides of the same outward code do not feel alike.
The full postcode
The full postcode, such as SW4 9AB, is the unit the public scores are stored against. Zoom in and the dots become these units. Click one to read the scores and, if you live there or you have visited, to leave a note.
Streets are the lines
Postcodes are points because the public lookup we use is a centroid, not a property boundary. Streets are the coloured lines. You can rate a street on its own, which matters when one road inside a postcode is quieter than the next.
Search from the London map with a street name, an outward code, a sector, or a full postcode.