DIGIPIN glossary.
Every term you'll meet in the world of digital addresses — defined plainly, in one place.
A
Aadhaar address
The address linked to a citizen's Aadhaar identity record. It is the official address for most government services in India and is distinct from a DIGIPIN, which only encodes a location.
Address standardisation
The process of converting messy, free-text addresses into a consistent structured format. DIGIPIN can be one component of a standardised record, capturing precise location alongside structured street and building data.
Address verification
Confirming that an address is correct and that the person claiming it actually lives there. DIGIPIN, paired with a phone OTP or a visit, can serve as one piece of evidence.
B
Bounding box
The rectangle of latitude and longitude inside which a geographic area lies. The DIGIPIN algorithm starts from the bounding box of India and recursively subdivides it.
C
Coordinate
A pair of numbers (latitude, longitude) that identifies a point on Earth. DIGIPIN converts coordinates into a short alphanumeric code.
D
DIGIPIN
A 10-character alphanumeric code released by India Post that identifies a 4 m × 4 m square anywhere in India. Short for Digital Postal Index Number.
Department of Posts (India Post)
The agency of the Government of India that operates the country's postal service and publishes the DIGIPIN standard.
E
Encoding (DIGIPIN)
The process of converting a latitude/longitude pair into a DIGIPIN code by repeatedly subdividing the bounding box of India.
G
Geocode
A code or set of coordinates that identifies a location on Earth. DIGIPIN is a geocode for locations inside India.
Reverse geocode
The process of converting a coordinate or geocode back into a human-readable address (street, locality, city). Often used together with DIGIPIN to translate a code into something a delivery agent can recognise.
Grid (DIGIPIN)
The hierarchical 4 × 4 division of India used by the DIGIPIN algorithm. After 10 levels of subdivision, each cell is approximately 4 m on each side.
GPS
The Global Positioning System — the satellite-based system that lets devices determine latitude and longitude. Most ways of finding a DIGIPIN rely on GPS to capture the input coordinates.
I
IIT Hyderabad
The Indian Institute of Technology Hyderabad, an academic partner in the development of the DIGIPIN standard.
India Post
The common name for the Department of Posts, Government of India.
ISRO
The Indian Space Research Organisation. The National Remote Sensing Centre, under ISRO, contributed to the development of DIGIPIN.
L
Last-mile delivery
The final leg of a delivery journey — from a local hub to the recipient's door. DIGIPIN is designed to make this leg faster and more reliable.
Latitude / Longitude
A pair of numbers that uniquely identifies a point on Earth's surface. DIGIPIN encodes a latitude/longitude into a much shorter code.
N
Nominatim
An open-source reverse geocoding service built on OpenStreetMap data. Often used alongside DIGIPIN to convert a coordinate into a readable address.
O
OpenStreetMap
A free, community-built map of the world. Many DIGIPIN tools display results on top of OpenStreetMap tiles.
OG image
Open Graph image — the preview image that shows when a page is shared on social media or messaging apps. Each DIGIPIN article can have its own OG image.
P
PIN code
Postal Index Number — the 6-digit code introduced by India Post in 1972 to identify a postal area. PIN codes route mail to the right town; DIGIPIN refines the last mile.
Plus Code
An open location code system developed by Google. Plus Codes work globally; DIGIPIN works only inside India.
Postal address
A human-readable address — name, street, locality, city, state, PIN code — used to send mail. DIGIPIN supplements but does not replace it.
R
Rural addressing
The problem of identifying buildings in areas without named streets, numbered houses, or formal postal infrastructure. DIGIPIN is particularly useful here.
U
Unique address
An address that identifies exactly one location with no ambiguity. A DIGIPIN comes close at the 4 m × 4 m grid level.
W
What3Words
A commercial global addressing system using three-word combinations to identify 3 m × 3 m squares anywhere on Earth. Comparable in idea to DIGIPIN, but global and proprietary rather than national and open.