Technical Documentation

How DIGIPIN Works

Understanding India's National Level Addressing Grid - A comprehensive guide to the technical architecture, design principles, and implementation of the Digital Postal Index Number system.

Core Concept

DIGIPIN divides India's geographical territory into uniform 4-meter by 4-meter units, each assigned a unique 10-digit alphanumeric code.

Uniform Grid System

The entire geographical territory of India is divided into uniform 4m × 4m units using a hierarchical grid system with 10 levels of precision.

Alphanumeric Encoding

Each unit receives a unique 10-digit code derived from latitude and longitude coordinates using 16 symbols: 2-9, C, F, J, K, L, M, P, T.

Offline Capability

DIGIPIN functions as an offline addressing reference system with built-in directional properties and logical naming patterns.

Bounding Box Coverage

Longitude Range63.5° - 99.5° E
Latitude Range2.5° - 38.5° N
Total Coverage36° × 36°
Coordinate SystemEPSG:4326 (WGS84)
Final Grid Size3.8m × 3.8m

Grid Labeling System

DIGIPIN uses a 4×4 grid with 16 symbols arranged in an anticlockwise spiral pattern for directional properties.

16-Symbol Grid Pattern

F
C
9
8
J
3
2
7
K
4
5
6
L
M
P
T

Symbols arranged in anticlockwise spiral pattern

Directional Properties: Adjacent cells have consecutive symbols
Hierarchical: Same pattern applied at all 10 levels
Intuitive: Human-readable format with logical naming

Symbol Selection Criteria

Phonetic Clarity

Symbols chosen for clear pronunciation and minimal confusion in verbal communication.

Visual Distinction

Characters selected to avoid visual confusion and ensure clear digital representation.

International Standards

Symbols compatible with international addressing standards and digital systems.

Hierarchical Encoding Process

DIGIPIN generation follows a 10-level hierarchical process, progressively narrowing down from country level to precise 3.8m location.

Example: Dak Bhawan, New Delhi

28.622788°N, 77.213033°E
39J-49L-L8T4
1
3
1000 km
2
9
2.25°
250 km
3
J
33.75′
62.5 km
4
4
8.44′
15.6 km
5
9
2.11′
3.9 km
6
L
0.53′
1 km
7
L
0.13′
250 m
8
8
0.03′
60 m
9
T
0.5′′
15 m
10
4
0.12′′
3.8 m

DIGIPIN Precision Levels

LevelCode LengthGrid SizeDistanceUse Case
11 digit1000 kmCountry/Region level
22 digits2.25°250 kmState level
33 digits33.75′62.5 kmDistrict level
44 digits8.44′15.6 kmCity level
55 digits2.11′3.9 kmLocality level
66 digits0.53′1 kmNeighborhood level
77 digits0.13′250 mBlock level
88 digits0.03′60 mBuilding level
99 digits0.5′′15 mPrecise area
1010 digits0.12′′3.8 mExact location

Key Properties of DIGIPIN

DIGIPIN is designed with specific properties that make it ideal for India's addressing needs.

Geographic Precision

Contains exact geographic location with ability to extract latitude and longitude coordinates with low computational complexity.

India-Specific Design

Designed specifically for Indian context, covering all points of interest including maritime regions and densely populated areas.

Human-Readable Format

Intuitive alphanumeric format with built-in sense of directionality and adjacency for easy navigation and understanding.

Future-Proof Infrastructure

Independent of land use patterns and built structures. Remains constant despite changes in roads, buildings, or administrative boundaries.

Efficient Representation

Optimized length design providing efficient digital representation of addresses while maintaining precision and usability.

Privacy Respecting

Represents only location information without storing any personal data, ensuring complete privacy protection for users.

Technical Implementation

DIGIPIN includes comprehensive programming functions for encoding and decoding coordinates.

Encoding Function

Get_DIGIPIN(lat, lon)

Takes latitude-longitude coordinates as input and encodes them into a 10-digit alphanumeric DIGIPIN code.

  • Input: Decimal degrees (lat, lon)
  • Output: 10-character DIGIPIN code
  • Precision: Up to 5 decimal places

Decoding Function

Get_LatLng_By_Digipin(code)

Takes a 10-digit alphanumeric DIGIPIN code as input and decodes it into degree-decimal coordinates.

  • Input: 10-character DIGIPIN code
  • Output: Latitude, Longitude coordinates
  • Accuracy: Center point of 3.8m grid

Boundary Conditions

Grid Line Coincidence Rules

  • Vertical lines: Assign to right-side (eastward) grid
  • Horizontal lines: Assign to up-side (northward) grid
  • Intersections: Assign to top-right grid

Boundary Exceptions

  • Top boundary (38.5°N): Assign to bottom-side grid
  • Right boundary (99.5°E): Assign to left-side grid

Ready to Experience DIGIPIN?

Join the digital addressing revolution. Experience India’s next-gen addressing grid, based on the DIGIPIN framework, today.