Why is there no basemap (roads, place names, satellite imagery) behind the shapes?

Adding a real basemap means fetching map tile images from a third-party server on every pan or zoom, which is exactly the kind of network request this site never makes. This tool draws only the shapefile's own geometry, projected to fit its own bounding box, on a plain background with a light graticule border, that's a deliberate, honest design choice, not a missing feature.

Why does this need a .zip instead of just a .shp file?

A shapefile is really a small bundle of files: .shp holds geometry, .dbf holds the attribute table, .shx/.prj are optional index/projection files. This tool needs at least .shp + .dbf zipped together, a bare .shp alone isn't accepted.

How is the geometry positioned in the preview?

By a simple linear fit: the shapefile's overall longitude/latitude bounding box is stretched to fill the SVG viewBox, with latitude flipped since SVG's y-axis grows downward while latitude grows upward. It's a straightforward bounding-box fit, not a real map projection.

What happens with multiple layers in one zip?

Every layer's features are merged and drawn together in the same preview, so you can see the combined geometry from a multi-layer zip in one view.

Shapefile Viewer - Preview a Zipped Shapefile's Geometry

Overview

Introduction

Sometimes you don't want to convert a shapefile to GeoJSON text, you just want to see what shape it actually contains, without opening a full desktop GIS application.

Shapefile Viewer uploads a zipped shapefile and draws its geometry directly, points, lines, and polygons rendered as plain SVG shapes fit to their own bounding box.

What Is Shapefile Viewer?

A client-side shapefile previewer: shpjs parses the uploaded zip into GeoJSON internally, and a shared SVG-rendering helper projects every coordinate to fit a fixed viewBox, drawing lines/polygons as SVG paths and points as small circles.

It's intentionally not a full interactive map, there's no panning, zooming, or basemap imagery, just a straightforward visual check of the shapes a shapefile contains.

How Shapefile Viewer Works

The uploaded zip is read as raw bytes and handed to shpjs, which unzips it, parses .shp geometry and .dbf attributes, and returns GeoJSON (merging every layer if the zip bundles more than one).

The resulting FeatureCollection is passed through this category's shared geoJsonToSvgPaths helper, which computes the overall longitude/latitude bounding box, linearly maps it to the SVG viewBox, and returns ready-to-render path and point coordinates.

When To Use Shapefile Viewer

Use this whenever you want a quick visual check of a shapefile's geometry, its rough shape, extent, and feature count, without exporting anything or opening desktop GIS software.

It's especially handy for a first look at a shapefile you didn't create yourself, to confirm it contains what you expect before converting or processing it further.

Often used alongside Shapefile to GeoJSON Converter and GeoJSON Viewer.

Features

Advantages

Runs entirely client-side, your shapefile data never leaves your browser and no map tiles are fetched.
Instant visual feedback on a shapefile's geometry without needing GIS desktop software.
Handles multi-layer zips by drawing every layer's merged geometry together.

Limitations

No panning, zooming, or interactivity, it's a static preview fit to the data's bounding box.
No basemap imagery (roads, place names, terrain), by deliberate design, see the FAQ above.
Only accepts a zipped bundle, a bare .shp file alone isn't supported.

Examples

A zip with a handful of polygon features

Input

districts.zip (containing districts.shp, districts.dbf)

Output

An SVG preview showing each district's polygon outline fit to the data's combined bounding box, plus a legend reading "5 features, Polygon"

The legend reports the feature count and geometry type(s) found, while the SVG shows the actual shapes projected to fill the preview area.

Best Practices & Notes

Best Practices

Use this before Shapefile to GeoJSON Converter as a quick sanity check that the zip actually contains what you expect.
Check the legend's geometry type list if a preview looks empty, an unsupported or unexpected geometry type may be present.
Include a .prj file in your zip for shapefiles in a non-standard projection, for correctly shaped (if not basemap-aligned) output.

Developer Notes

`readShapefileForViewer` in `shapefile-viewer.ts` shares its parsing logic (normalize shpjs's single-or-array result, flatMap into one FeatureCollection) with `shapefile-to-geojson-converter.ts`, but returns the parsed `FeatureCollection` object directly rather than a JSON string, since the component feeds it straight into the shared `geoJsonToSvgPaths(featureCollection, {width, height, padding})` helper from `geo-svg-render.ts` rather than exporting text.

Shapefile Viewer Use Cases

Quickly checking what a shapefile zip actually contains before converting or processing it further
Visually confirming a multi-layer shapefile zip's combined extent and feature count
Sanity-checking shapefile geometry without installing desktop GIS software

Common Mistakes

Expecting to see roads, place names, or satellite imagery behind the shapes, this viewer deliberately draws only the shapefile's own geometry, never fetched basemap tiles.
Uploading a bare .shp file without its accompanying .dbf zipped alongside it, the zip needs at least both to be read correctly.

Tips

If the preview looks unexpectedly tiny or off in one dimension, check whether your data spans a very different range in longitude versus latitude, the bounding-box fit stretches to the viewBox regardless of aspect ratio.
Use Shapefile to GeoJSON Converter afterward once you've confirmed the shape looks right, to get the actual GeoJSON text out.

Shapefile Viewer