What3words is a proprietary geocode system designed to identify any location with a resolution of about 3 metres (9.8 ft). It is owned by What3words Limited, based in London, England. The system encodes geographic coordinates into three permanently fixed dictionary words. For example, the front door of 10 Downing Street in London is identified by ///slurs.this.shark.[1]

What3words Ltd.
Founded2013; 9 years ago (2013)
HeadquartersLondon, England, UK

What3words differs from most location encoding systems in that it uses words rather than strings of numbers or letters, and the pattern of this mapping is not obvious; the algorithm mapping locations to words is proprietary and protected by copyright.[2]

The company has a website, apps for iOS and Android, and an API for bidirectional conversion between what3words addresses and latitude/longitude coordinates.


Founded by Chris Sheldrick, Jack Waley-Cohen, Mohan Ganesalingam and Michael Dent, what3words was launched in July 2013.[3][4] Sheldrick and Ganesalingam conceived the idea when Sheldrick, working as an event organizer, struggled to get bands and equipment to music venues using inadequate address information.[5] Sheldrick tried using GPS coordinates to locate the venues, but decided that words were better than numbers after a one-digit error led him to the wrong location. He credits a mathematician friend for the idea of dividing the world into three-metre squares, and the linguist Jack Waley-Cohen with using memorable words.[6] The company was incorporated in March 2013[7] and a patent application for the core technology filed in April 2013.[8] In November 2013, what3words raised US$500,000 of seed funding;[9]

Following initial unsuccessful attempts to become profitable as a consumer-focused offering, What3words switched to a business-to-business model.[10] In January 2018, Mercedes-Benz bought approximately 10% of the company and announced support for What3words in future versions of the Mercedes-Benz User Experience infotainment and navigation system.[11] The A-Class, launched in May 2018, became the first vehicle in the world with What3words on board.[12]

In March 2021 it was announced that ITV plc had bought a £2.7 million stake in What3words to gain access to advertising space.[13]

In 2018 the company had a turnover of £274,000 and lost £11M.[10] In the year ending December 2019, the company lost £14.5M and had reported assets of £24.7M.[13] By January 2020 the company had reached 100 employees and raised over £50M from investors.[10]

Design principlesEdit

What3words divides the world into a grid of 57 trillion 3-by-3-metre squares, each of which has a three-word address. The addresses are available in forty-seven languages.[14][15]

Translations are not direct, as direct translations to some languages could produce more than three words. Rather, territories are localised considering linguistic sensitivities and nuances.[16]

Each what3words language uses a list of 25,000 words (40,000 in English, as it covers sea as well as land). The lists are manually checked to remove homophones and offensive words.[16]

What3words originally sold "OneWord" addresses, which were stored in a database for a yearly fee,[17] but this offering has been discontinued.[18]

The company states that densely populated areas have strings of short words due to more frequent usage; while less populated areas, such as the North Atlantic, use more complex words.[16][6]

In an interview with the BBC, co-founder Sheldrick said: "Whilst the overwhelming proportion of similar-sounding three-word combinations will be so far apart that an error is obvious, there will still be cases where similar sounding word combinations are nearby."[19]

According to Rory Sutherland of Ogilvy (an advertising agency employed by what3words)[20] in an op-ed piece for The Spectator, the system's advantages are memorability, error-detection, non-ambiguity of words for most everyday and non-technical uses, and voice input.[21]

Emergency services useEdit

In February 2020, in Scotland, the system was first used by stranded walkers.[22] That month, in Australia, it was also first used in a rescue operation.[23]


Not an open standardEdit

Supporters of open standards criticise the What3words system for being controlled by a private business and the software for being patented and not freely usable.[24]

The company has pursued an assertive policy of issuing copyright claims against individuals and organisations that have hosted or published files of the What3words algorithm or reverse-engineered code that replicates the service's functionality, such as the free and open source implementation WhatFreeWords.[25] The whatfreewords.org website was subsequently taken down following a Digital Millennium Copyright Act (DMCA) take-down notice issued by What3words. This has extended to removing comments on social media which refer to unauthorised versions. In late April 2021, a security researcher was subjected to the threat of a lawsuit from What3words, stating that linking to the open source reimplementation "WhatFreeWords" violates the company's copyright.[26] "The letter also demanded that he disclose to the [company's lawyers] the identity of the person or people with whom he had shared a copy of the software, agree that he would not make any further copies of the software and to delete any copies of the software he had in his possession."[26]

Words are not culturally neutralEdit

Open standards advocate and technology expert Terence Eden has questioned the cultural neutrality of using words rather than the numbers generated by map coordinates. "Numbers are (mostly) culturally neutral." he said, "Words are not. Is mile.crazy.shade a respectful name for a war memorial? How about tribes.hurt.stumpy for a temple?" [27]

Similar addresses can be closeEdit

The company believes that any slightly incorrectly entered three-word combination will be obvious as a mistake. However, security researcher Andrew Tierney demonstrated in 2021 that the What3words algorithm does not sufficiently protect against confusion between nearby locations because it may assign words that are similarly spelled or pronounced, which can limit the value of the system when a precise and unambiguous location is required, like safety-critical applications.[28] Analysis by Tierney showed that close repetitions and the use of plurals occur in physically close locations. The company says that this has a one in 2.5 million chance of occurrence,[29] but Tierney's analysis has highlighted areas where the odds are around 1 in 500.[28]

That similar addresses are purposely far away from each other is seen by others as a disadvantage.[30]

Incorrect addressesEdit

In June 2021 Mountain Rescue England and Wales raised concerns about the credibility of reported What3words coordinates, following incorrect information being given about 45 locations over 12 months. Spelling issues and local accents were reported as being part of the problem.[31]


The site has been parodied by others who have created services including What3Emojis[32] using emojis, What3Birds[33] using British birds, What3fucks[34] using swear words, Four King Maps[35][36] also using swear words (covering only the British Isles), and What3Numbers[37] using OpenStreetMap tile identifiers.


In popular cultureEdit

In 2016, What3words appeared in a plotline of The Last Ship.[41][better source needed]

In 2018, What3words appeared in a plot line of NCIS: Los Angeles.[42]

In 2021, a fictional variation of What3words appeared in episode 179 of The Blacklist.[citation needed]

See alsoEdit


  1. ^ Leatherdale, Duncan (15 August 2019). "What3words: The app that can save your life". BBC News. Retrieved 31 January 2021.
  2. ^ "What3Words sent a legal threat to a security researcher for sharing an open-source alternative". TechCrunch. Retrieved 11 November 2021.
  3. ^ "'What3Words' Wants To Replace Postcodes With Words – For The Entire Globe". HuffingtonPost. 2 July 2013.
  4. ^ "Location-Pinpointing Startup what3words Sells 10,000+ OneWord Map-Pins In First Week". Techcrunch. 8 July 2016.
  5. ^ Lanks, Belinda (11 October 2016). "This App Gives Even the Most Remote Spots on the Planet an Address". Magenta.as.
  6. ^ a b Margolis, Johnathan (20 October 2015). "What3Words: new tech that will find any location". Financial Times. Retrieved 15 June 2021.
  7. ^ "WHAT3WORDS LIMITED - Overview (free company information from Companies House)". Companies House.
  8. ^ "A Method and Apparatus for Identifying and Communicating Locations". World Intellectual Property Organization.
  9. ^ "Startup what3words gets USD 500,000 in seed round". Venture Capital Post.
  10. ^ a b c Sam Shead (15 January 2020). "A navigation startup pivots and grows, but profitability is still down the road". Business Insider.
  11. ^ "Why Daimler Invested in a Startup That Has Labeled the World With Unique Three-Word Addresses". Fortune. 11 January 2018.
  12. ^ Brecht, Michael (5 April 2018). "What3words: Diese Ortungssoftware gibt es bald serienmäßig in Daimlers A-Klasse". Die Welt.
  13. ^ a b Stephen Lepitak (25 March 2021). "British Broadcaster ITV Invests $2.7 Million in Location Finding Platform What3words". Adweek.
  14. ^ Feng, Rebecca (11 June 2016). "Startup What3words Aims To Give Billions Of People One Thing They Don't Have: An Address". Forbes. Retrieved 16 November 2019.
  15. ^ Harris, Harry (30 April 2015). "Every Three-Metre Square on the Planet Now Has a Unique Address". Vice Media. Retrieved 16 June 2021.
  16. ^ a b c Lo Dico, Joy (6 February 2021). "Postcodes from the edge: how an upstart app is changing the world's addresses". Financial Times. Retrieved 15 June 2021.
  17. ^ Lomas, Natasha (8 July 2013). "Location-Pinpointing Startup what3words Sells 10,000+ OneWord Map-Pins In First Week". TechCrunch.
  18. ^ "Why can't I buy my own words or change some of the words?". what3words.
  19. ^ Wakefield, Jane (29 April 2021). "App used by emergency services under scrutiny". BBC News. Retrieved 16 June 2021.
  20. ^ "Addressing The Problem". Design and Art Direction. Retrieved 16 June 2021.
  21. ^ Rory Sutherland (25 October 2014). "The best navigation idea I've seen since the Tube map". The Spectator. Archived from the original on 5 January 2015.
  22. ^ "Walkerstime in trainers rescued in Ben Nevis blizzard". BBC News. BBC. 11 February 2020.
  23. ^ Power, Julie (18 May 2020). "Three random words saved Cornelia on a cold wet day of bushwalking". Sydney Morning Herald.
  24. ^ "What3words: 'Life-saving app' divides opinion". BBC News. 21 September 2019.
  25. ^ "DMCA takedown of code on Github". GitHub. 5 July 2016.
  26. ^ a b Whittaker, Zack (30 April 2021). "What3Words sends legal threat to a security researcher for sharing an open-source alternative".
  27. ^ "What3words: 'Life-saving app' divides opinion". BBC News. 20 September 2019. Retrieved 3 October 2020.
  28. ^ a b Tierney, Andrew (29 April 2021). "Why What3Words is not suitable for safety critical applications".
  29. ^ "App used by emergency services under scrutiny". BBC News. 29 April 2021. Retrieved 29 April 2021.
  30. ^ "What3Words is quite a find". The Boston Globe. 1 July 2016.
  31. ^ Wakfield, John (1 June 2021). "Rescuers question what3words' use in emergencies". BBC. Retrieved 1 June 2021.
  32. ^ "what3emojis". what3emojis.com.
  33. ^ "Location Encoding Systems". checkmypostcode.uk. What3Birds...is a parody of the commercial What3Words system, which isn't suitable for this website as it doesn't have a published, open source algorithm. It does, though, work - every postcode on this website has a unique, three bird code. The list of birds was taken (in simplified form) from the British Ornithologists' Union's official list of birds recorded in Britain.
  34. ^ "what3fucks". Archived from the original on 5 December 2019.
  35. ^ "Four King Maps".
  36. ^ Corfield, Gareth (14 August 2021). "Tired: What3Words. Wired: A clone location-tracking service based on FOUR words – and they are all extremely rude". The Register. London. Retrieved 24 December 2021.
  37. ^ "what3numbers". Github.io.
  38. ^ Diaz, Ann-Christine (26 June 2015). "What3Words Innovation Grand Prix Cannes – Special: Cannes Lions – Advertising Age". adage.com.
  39. ^ "San Jose: Tech awards honor an array of laureates". Mercury News. 12 November 2015.
  40. ^ "Awards". Royal Institute of Navigation. 2019.
  41. ^ "3 words to find a warship – TNT's The Last Ship | what3words". what3words.com. Retrieved 11 December 2021.
  42. ^ Burn-Callander, Rebecca. "What3words maps a future with true pinpoint accuracy". ISSN 0140-0460. Retrieved 29 March 2021.

External linksEdit