Curated list · updated 2 November 2026
Best Free Coordinate Conversion Tools
Conversion is easy; the mistakes happen before and after it. Confirm the datum and the axis order, then convert.
Coordinate conversion looks like pure arithmetic, and it mostly is — which is why the failures are so confusing when they happen. A swapped latitude and longitude produces a perfectly valid coordinate in the wrong hemisphere, and a NAD27 value converted as if it were WGS84 shifts by tens of metres without any error message.
The tools below convert in both directions and, more usefully, tell you which format they recognised in the first place.
- 1
Coordinate Converter
Decimal degrees, DMS, DMM, UTM, MGRS, Plus Codes and geohash in one place.
- 2
Coordinate Parser
Paste an unknown pair and have the format named before conversion.
- 3
DMS to Decimal
The single-step conversion for charts and legacy records.
- 4
UTM Converter
Zone-aware UTM conversion, including the Norway and Svalbard exceptions.
- 5
MGRS Converter
Military grid references with selectable precision.
- 6
Plus Code Finder
Open Location Codes for places without a street address.
- 7
Latitude Longitude Validator
Check ranges and signs across a list before you import it anywhere.
How this list was chosen
Ranked by how often each format appears in real datasets, then by whether the tool also validates. All conversions run locally on WGS84.
MapBench is a single site, so this is a recommendation list rather than an independent market survey. Every listed tool is free, needs no account, and publishes the method behind its result.
Browse the full clusters
Read before you rely on the number
- Understanding GPS Coordinates: Formats, Datums and Precision
A practical guide to latitude/longitude: what decimal degrees and DMS really mean, why datums matter, and how many decimal places you actually need.
- What County Am I In? How County Lookup Actually Works
County lines are legal boundaries, not vibes. How map tools resolve a point to a county — and why borders, unincorporated areas, and bad GPS fix create surprises.
- KML vs. GeoJSON vs. GPX: Choosing the Right Map File Format
The practical differences between three common geographic file formats — when to use each, what can be lost in conversion, and how to move between them.
Common questions
Which coordinate format should I use?
Decimal degrees for data and databases, DMS for anything read aloud or copied from a chart, UTM or MGRS for field work on a grid, and Plus Codes for places without addresses.
Is a conversion lossless?
Yes at the precision you display, provided the datum is unchanged. Converting between datums is a different operation and can shift positions by tens of metres.