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Serac
Serac

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I Built a Free, Privacy-First Coordinate Converter That Runs Entirely in Your Browser

If you've ever worked with GPS data, GIS pipelines, or geospatial APIs,
you know the pain: your data is in UTM, your map expects Decimal Degrees,
your colleague sends you MGRS, and your database stores Geohash.

Switching between coordinate formats is a small but constant friction
point for developers, surveyors, drone operators, and anyone doing field
work. Most online tools require sign-ups, ship your data to a server,
or support only 2–3 formats.

So I built CoordConv — a fast,
browser-based coordinate converter that handles 7 formats in one place.


What It Supports

Format Example Common Use
DD Decimal Degrees 40.7128, -74.0060 Google Maps, GPS
DMS Degrees Minutes Seconds 40°42'46"N 74°00'21"W Aviation, nautical
DDM Degrees Decimal Minutes 40°42.767'N Marine, geocaching
UTM 18T 583960 4507523 Surveying, topo maps
MGRS 18TWL8395907523 Military, SAR
Plus Code 87G7PX7V+4H Delivery, field ops
Geohash dr5regw3pg Spatial indexing, dev tools

Key Features

  • Instant conversion — paste any format, get all 7 outputs at once
  • 🗺️ Interactive map preview — verify your location visually before copying
  • 📋 One-click copy for every output format
  • 📦 Batch Converter — handles CSV files or pasted tables with hundreds of rows
  • 🔄 Lat/Lon and Lon/Lat order toggle (because GeoJSON vs GPS is a real gotcha)
  • 🎯 6 decimal place precision (~±0.11 meters accuracy)

Try It

👉 coordconv.com

Specific tools:


Happy to answer questions about how the projection math works under the
hood, or how to handle the WGS84 vs NAD83 vs GCJ-02 datum differences
in your own projects. Drop them in the comments! 🗺️

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