Available CSV files in ./csv_input
    Click 'Load CSV' to browse available files
    Layer
    Display Regions
      Polygon
      Split Polygon:
      Grid Split: ×
      Vertices
      Layer
      Label
      Redistricting
      + Created: 0 Rem: 0
      Total Population
      Allocated Seat
      Quota
      Boundary
      Current ward
      Ward colour
      Red ▾
      Draft electorate 0
      Variance −100.00%
      Wards
      No wards saved yet.
      Map shows one merged unit per County. Group counties into a constituency the same way you group polygons into a ward.
      + Created: 0 Rem: 0
      Total Population
      Allocated Seats
      Quota
      Current constituency
      Constituency colour
      Red ▾
      Draft population 0
      Variance −100.00%
      Constituencies
      No constituencies saved yet.
      Measure
      Click the map to start measuring
      Click circle to remove · Drag to move · Esc to exit
      SVG Street Map
      Rotate 0°
      Scale 100%
      Offset X 0
      Offset Y 0
      Opacity 35%
      Change Population Density
      Value must be a number between 50 and 50,000.
      Select Location
      Select Type
      Split Polygon by OSM Districts
      Pan and zoom the map to position the green frame over your target area. The frame is sized to match the selected polygon's real-world dimensions.
      Data source:
      Road detail level:
      Remove vertices closer than m
      Click row to select/highlight on map
      Road tier
      Simplify
      m
      Min area
      m²
      Higher = fewer, larger districts
      No selection = apply to all
      Redistricting Rule — Population Quota
      Population Size Quota
      0 – 400,000
      400,001 – 650,000
      650,001 – 1,000,000
      1,000,000 +
      Redistricting Rule — Electoral Regions
      Electoral Regions
      Map Regions to Electoral Regions
      Load a CSV first.
      Seat Allocation
      Electoral Region Population Share Proportional Allocated