UTM & MGRS Coordinates

Buy it once, keep it. No subscription, no ads, no account – and everything works in Airplane Mode.

Zonepoint converts coordinates between WGS84, UTM, MGRS and Gauss-Krüger. Every calculation runs on the device. The app works entirely offline: the only thing it ever downloads is a map pack you choose – nothing else, and never on its own.

THE SELF-TEST – WHY YOU CAN TRUST THE NUMBERS
On demand, Zonepoint recomputes 52 published check points on your own device and reports the largest deviation for each transform family: UTM, transverse Mercator, MGRS, UPS and Gauss-Krüger. Across all 52 points the largest measured deviation stays under a tenth of a millimetre. You do not have to take our word for it – you can run it before you buy, and share the result as plain text.
The check points come from NGA GEOTRANS Gold Data and AdV BeTA2007 test data. Neither organisation endorses this app.

FREE, PERMANENTLY
• Your position at once in WGS84 (decimal, degrees/minutes, degrees/minutes/seconds), UTM, MGRS and Gauss-Krüger
• Convert: type or paste, in any of those formats
• Messy input is parsed and the possible readings are ranked, with every assumption named
• Copy and share as text. Any saved point, any time, permanently
• A target point with distance and true bearing
• Up to ten waypoints
• Fix accuracy in metres, age of fix, altitude above mean sea level and ellipsoidal height
• A built-in world overview map – always there, with or without a map pack
• A grid plot with UTM grid lines, a scale bar and grid convergence – no basemap, no connection
• The self-test, and a page listing everything in this app that touches the network
• Night mode in red for dark adaptation, and sunlight mode for glare
• Full German and English interfaces, each with correct number formatting

PRO – one payment, no subscription
• Unlimited waypoints, in folders, with notes
• Import and export: GPX, KML and CSV
• Multi-leg routes with distance and bearing per leg
• Offline map packs for Germany, Austria and the United States: download one over Wi-Fi, then the map draws real streets in Airplane Mode with no connection at all
• A UTM or MGRS grid overlay on the map, from 10 km down to 100 m
• Batch conversion of a whole pasted list
• Datum and ellipsoid selection, each with its accuracy stated
• Neighbouring-zone override at zone boundaries, and your own copy formats

WHY ONE PRICE AND NOT A SUBSCRIPTION
Geodesy has not changed since the datums were defined, so the price does not recur either. Zonepoint asks once, and the unlock is permanent. The purchase restores, and it is enabled for Family Sharing.

HONEST ABOUT ACCURACY
Every conversion states its own accuracy in metres rather than presenting a number with no error budget. Zonepoint is a tool for working in the field. It does not replace a survey.

PRIVACY
No account, no sign-in, no analytics, no tracking, no ads. There is nothing to transmit, because everything stays on the device. The only connection the app ever opens is the download of a map pack you asked for – and nothing is uploaded.

Map data © OpenStreetMap contributors, ODbL. World overview: Natural Earth.