QGIS Plugin

SOI TopoSheet Number Calculator

Version 4 — An advanced Python plugin for QGIS that automatically calculates and generates Survey of India topographic map sheet numbers.

Install from QGIS Plugin Repository Download Documentation (.docx)

TopoSheet Number Calculator Version 4 is an advanced Python plugin developed for QGIS that automatically calculates and generates map sheet numbers for the Survey of India (SOI) Topographical Maps. The plugin is designed to assist researchers, GIS professionals, planners, surveyors, and students in identifying the correct topographic map sheets corresponding to any spatial dataset within the Indian region.

The plugin computes the boundaries of all relevant map sheets for the extent of the selected input layer and creates a new polygon layer representing the sheet boundaries. Each generated polygon is automatically labelled with its corresponding sheet number, enabling easy visualization and identification of map coverage.

This plugin can be installed directly from the QGIS Manage and Install Plugins options under the experimental plugins category, or downloaded from the QGIS Plugin Repository.

Supported Map Series

Old Series Maps

India and Adjoining Countries Series Maps

Open Series Maps (OSM)

Introduced after 2005, based on UTM projection and WGS 84 Datum

The plugin can calculate sheet numbers for all available map scales in both map series. It dynamically generates sheet boundaries and visually distinguishes the sheets that intersect with the input features.

Key Features

Automatic calculation of Survey of India Toposheet numbers
Supports both Old Series Maps and Open Series Maps (OSM)
Generates polygon boundaries for all relevant map sheets
Automatic labelling of generated sheets with map sheet numbers
Highlights intersecting sheets in light green; non-intersecting surrounding sheets in yellow
Generated sheet boundary layers are automatically added to the QGIS Layer Panel
Supports Point, Line, and Polygon layer geometry types
Compatible with Geographic CRS (EPSG:4326) and UTM projected coordinate systems
User-friendly interface suitable for both beginners and advanced GIS users

Coordinate Reference System Requirements

The plugin primarily works with datasets in the Geographic Coordinate Reference System using EPSG:4326 — WGS 84.

Version 4 also supports layers having projected coordinates in the Universal Transverse Mercator (UTM) projection system. The plugin automatically processes the layer extent and computes the appropriate map sheets accordingly.

For accurate results, the spatial extent or coordinate values of the input layers must lie within the geographical region of India.
TopoSheet Number Calculator Plugin - User Interface

Fig.1 — User Interface of the Plugin

Workflow

1. Select the desired input layer in QGIS.
2. Choose the map series type — Old Series Maps or Open Series Maps (OSM).
3. Select the required map scale.
4. Run the plugin.
5. The plugin automatically:
  • • Computes the sheet boundaries
  • • Generates sheet polygons
  • • Labels the polygons with sheet numbers
  • • Highlights intersecting sheets
  • • Adds the generated layer to the QGIS project

Applications

Topographical map indexing
GIS-based planning and analysis
Field survey preparation
Academic and research work
Geospatial data organization
Cartographic applications
Remote sensing and terrain studies

TopoSheet Number Calculator Version 4

Significantly simplifies the otherwise time-consuming process of manually identifying Survey of India topographic sheets and provides an efficient GIS-based solution within the QGIS environment.