GIS Tools

101 browser-based geospatial utilities — convert between GeoJSON, KML, GPX, Shapefile, and GeoTIFF; run spatial analysis with Turf.js; render WebGL maps with MapLibre GL; and process raster DEMs for hillshade, slope, and NDVI — all client-side.

Full-Stack Software

What it is

G IS Tools is a free, browser-based geospatial platform with 101 specialized tools organized across eight categories: import and export, map viewing, query and filter, coordinate reference systems and projections, vector editing, geoprocessing, raster analysis, and spatial analysis. The platform handles the full range of geospatial formats — GeoJSON, Shapefile, KML, KMZ, GPX, CSV, WKT, TopoJSON, FlatGeobuf, PMTiles, MBTiles, Mapbox Vector Tiles, and GeoTIFF — and runs entirely in the browser using WebGL-powered map rendering via MapLibre GL JS, spatial operations via Turf.js, coordinate transformations via Proj4js, and raster processing via GeoTIFF.js. The site is available in seven languages. There are no accounts, no uploads, and no server-side computation. GIS Tools grew directly out of the geospatial work Stephen Taylor has done for over a decade — building interactive electoral maps with poll-by-poll resolution for the Stephen Taylor Data Project, geolocation-based heritage site discovery for Heritage Guide, and geophysics mapping applications for Dualem. The platform takes that accumulated GIS experience and makes the underlying operations available to anyone with a browser.

What I did

Built 101 geospatial tools across eight categories — from format conversion and coordinate reprojection to full geoprocessing operations, raster terrain analysis, network routing, and interactive thematic mapping
Implemented 32 geoprocessing tools powered by Turf.js — buffer, dissolve, clip, intersect, union, erase, Voronoi polygons, Delaunay triangulation, kNN nearest neighbor, density grids, convex and concave hull, point-in-polygon, line intersection detection, polygon overlap checking, and network-based shortest path routing with isochrone generation
Built 11 raster analysis tools using GeoTIFF.js — hillshade generation from DEMs, slope and aspect calculation, NDVI vegetation index from multispectral imagery, raster reclassification, zonal statistics within polygon boundaries, contour line generation, raster clipping, and resampling with nearest neighbor or bilinear interpolation
Built a WebGL-powered map viewer with MapLibre GL JS supporting multiple basemaps, categorical and graduated styling with Jenks natural breaks and quantile classification, heatmap and cluster rendering, label collision detection, and a print composer for export-ready map layouts with title, legend, and scale bar
Implemented coordinate reference system tools using Proj4js — including UTM conversion, EPSG reprojection, custom Proj4 string transforms, geodesic distance and area calculation, great circle routing, bearing and destination computation, datum shift visualization, and DD/DMS/MGRS format conversion
Built vector editing tools with full undo/redo history — feature drawing with snapping, move/rotate/reshape, topology repair, polygon cutting by line, feature merge and split, self-intersection fixing, and simplification preserving shared boundaries
Built query and filtering tools including a SQL-like attribute filter builder, spatial filtering by viewport or drawn polygon, full-text search with in-browser indexing, attribute and spatial joins, column statistics with histograms, data profiling reports, and de-duplication by coordinates or key field
Internationalized the full application into seven languages — English, French, German, Spanish, Chinese, Korean, and Japanese