What3words is a proprietary geocoding system that assigns a unique three-word identifier to every three-metre square on the Earth's surface. Unlike traditional address systems that rely on street names and numbers, or even postcodes that cover broader areas, what3words provides a highly precise location reference that is easy to remember and communicate verbally. The system divides the world into a grid of three-metre squares and assigns each square a fixed combination of three common words, such as 'table.lamp.chair'. This allows anyone to specify a location to within a few metres without needing a street address or coordinates.
What is What3words?
Developed by What3words Ltd, the system was created to solve the problem of inaccurate or missing addresses, particularly in rural areas, developing countries, or locations with no formal street naming. The three-word addresses are generated algorithmically and are unique across the globe. The words are chosen from a set of 40,000 English words, with similar words deliberately avoided to prevent confusion. Users can find the three-word address for any location using the what3words website or mobile app, and can also convert traditional coordinates or postcodes into three-word addresses. The system is free for personal use, but businesses pay for commercial licenses.
Relationship to UK Postcodes and Addresses
In the United Kingdom, the Royal Mail postcode system is the standard for mail delivery and location referencing. A typical UK postcode covers, on average, about fifteen addresses, but the area can vary from a single large building to a group of houses. What3words complements this system by providing a much finer level of granularity , each three-word address corresponds to a three-metre square, whereas a full postcode may cover a few hundred metres. For example, a what3words address can pinpoint the exact entrance of a building, a specific parking space, or a precise spot in a park, where a postcode would only identify the general area. This makes it particularly useful for emergency services, delivery drivers, and anyone needing to find an exact location quickly. However, what3words does not replace postcodes; rather, it offers an additional layer of precision. Many online maps and navigation apps now support what3words integration, allowing users to enter a three-word address instead of a traditional postcode or street address.
How It Relates to the UK Geography System
The UK Ordnance Survey grid and postcode system are the established methods for geographic referencing. What3words sits alongside these as a supplementary tool. It is not officially part of the UK postal addressing system, but has been adopted by some local authorities, emergency services, and businesses. For instance, the ambulance service in some regions uses what3words to locate callers in remote areas. It is also used for event management, logistics, and tourism. When researching an area, what3words can help identify specific points of interest, such as a hidden entrance or a meeting point, that may not be captured by a postcode or road name.
Why It Matters for Area Research
For someone researching an area, what3words offers a precise and human-friendly way to reference locations. It eliminates ambiguity found in vague descriptions or multiple locations sharing the same postcode. For example, a researcher mapping historical sites in a rural area can use what3words to record exact coordinates that are easy to share and recall. It also aids in comparing data across different sources: if two datasets use different coordinate systems, converting them to what3words can reveal matching locations. However, there are limitations. The system is proprietary, so its accuracy and availability depend on the company's continued operation. Moreover, the three-word addresses are random and do not convey any geographic relationship , nearby squares may have completely different word combinations, making it difficult to identify spatial patterns. Despite these drawbacks, what3words is a valuable tool for adding a layer of precise addressability to any location, and it is increasingly integrated into digital mapping and navigation systems.