Free tools
Polygon map validator and previewer
Paste your polygon GeoJSON to validate it and see a preview. If you need to draw shapes from scratch, use the MapsMaker editor instead.
If you’d rather draw, MapsMaker’s editor supports polygons and exports GeoJSON.
1,200+
Maps created
85k+
Locations mapped
<5 min
Avg. setup time
Validate and preview polygons
Paste boundary data to check validity and see it on a map.
- Paste Polygon or MultiPolygon GeoJSON
- See validation results instantly
- Preview on a static map and download the cleaned GeoJSON
When to use this vs the editor
This tool validates existing data — use the editor to draw new shapes.
- Use this when you already have GeoJSON from somewhere else
- Use the editor when you want to draw shapes manually
Tips for clean polygons
Catch common polygon issues before they show up on your live page.
- Close rings properly (first and last coordinate should match)
- Avoid self-intersections (they render unpredictably)
- Keep the polygon count low on a single page if you care about performance
Frequently asked questions
Can I style the polygon?
Yes—in the editor you can set fill, stroke, and opacity.
Does this support huge GeoJSON?
Very large overlays may fall back to base preview, but downloads still work.
Can I export GeoJSON from MapsMaker?
Yes—GeoJSON export includes shapes and markers.
Can I combine polygons with pins?
Yes—service maps often use both (zones + partner/office pins).
Is this tool free?
Yes, completely free with no signup required. When you’re ready to publish a full map, MapsMaker plans start at $15/month with a free trial.
Do I need to create an account?
No — this tool works without an account. You only need an account when you want to save, publish, or embed a map.
Draw and publish boundary maps
Use the MapsMaker editor to draw polygons, style zones, and embed on your site.