GNSS Engineering Tools
WGS84 Coordinate Converter
Switch instantly between every common coordinate format an antenna integrator runs into: decimal degrees for spreadsheets, DMS for surveyors, UTM for GIS, MGRS for defense and aviation, ECEF XYZ for raw GNSS calculations. All conversions assume the WGS84 datum — the reference frame every modern GNSS broadcasts in.
Six formats, one point
Edit any field and the others recompute live. Click a preset to start from a known landmark, or use your browser's geolocation to drop a pin where you are. Each format has a copy button, and the page URL stays in sync so you can share a permalink.
Decimal degrees (DD)
Degrees · Minutes · Seconds (DMS)
Degrees · Decimal Minutes (DDM)
UTM (Universal Transverse Mercator)
MGRS (Military Grid Reference)
ECEF — Earth-Centered Earth-Fixed
All conversions use the WGS84 datum — the global GNSS reference frame. Local datums (NAD83, ETRS89, GDA2020, CGCS2000, BJ54, etc.) differ from WGS84 by tens of centimetres to several metres in some regions; if you need a local-datum result, transform separately using your jurisdiction's published parameters or a grid-shift file.
Which format when?
Which format when?
Each coordinate format optimises for a different workflow. Pick the one your downstream tool expects and let this converter handle the rest.
Decimal degrees
Spreadsheet ingest, GeoJSON, Web mapping APIs, and most KML feeds. The default for any modern GIS pipeline. Always store at least 6 decimals — that's about 11 cm of precision at the equator.
Degrees · Minutes · Seconds
Field surveying, marine charts, aviation flight plans. Easier to read aloud over voice radio than 7-decimal floats. Many legacy data sources (USGS topo maps, marine pilot books) only quote DMS.
Decimal minutes
GPS handhelds, marine plotters, geocaching. A compromise between DD and DMS — keeps the integer-degree separation but uses a single decimal value for sub-degree precision.
UTM
Topographic mapping, civil engineering, military operations within a single zone. Linear metres on a flat grid make distance and area calculations trivial. Limited to 80°S–84°N latitude; UPS handles the polar caps.
MGRS
Defense, aviation, search-and-rescue. Compact alphanumeric strings (e.g., 33TUM1234567890) that survive voice transmission and short text messages without ambiguity. Built on top of UTM with letter codes for 100 km grid squares.
ECEF (XYZ)
Raw GNSS computations, satellite tracking, baseline solutions. The native frame in which receivers compute positions before projecting to lat/lon. Position differences in metres are direct — useful for static-baseline surveying and PPP processing.
FAQ
Frequently asked questions
Quick answers to the questions surveyors and GNSS integrators most often ask about coordinate formats.
How accurate is this converter?
Coordinate-to-coordinate conversions are exact to better than 10 cm globally. The UTM series uses Snyder's truncated forms (USGS Pro Paper 1395 §8) — accurate to a few centimetres anywhere outside the immediate polar regions. ECEF↔LLA uses Bowring's closed form, sub-millimetre for any altitude up to GEO orbit. Datum conversions are NOT performed; everything is WGS84.
Why does my converter show a different MGRS / UTM than this one?
Three usual culprits. First, the other tool may be using a different datum (NAD27 used by older USGS quad maps differs by tens of metres from WGS84). Second, MGRS has Norway- and Svalbard-specific zone widening at lat 56°–84°N — this tool uses the standard zone definition, which agrees with NGA outside those latitudes. Third, MGRS strings come in 4 precisions (1 m / 10 m / 100 m / 1 km / 10 km grid); compare the digit count before assuming a mismatch.
Can I share my point with a colleague?
Yes — every edit updates the page URL with ?lat=…&lon=…&alt=… so you can copy the address bar and send it. Opening that URL on any other browser drops the pin at the same point.
Why doesn't ECEF height match my GPS receiver's reported altitude?
Almost always because of the geoid. GNSS receivers measure ellipsoidal height (above WGS84) but commonly DISPLAY orthometric height (above mean sea level / EGM96 / EGM2008), differing by up to ±100 m globally. This converter only handles ellipsoidal height. Subtract the local geoid undulation if you need MSL.
Is my location data sent anywhere?
No. All conversions run entirely in your browser — no API calls, no server log, no analytics on the input values. The 'Use my location' button asks the browser for geolocation permission directly; it doesn't go through any third party.
Does this work for surveying-grade applications?
It's accurate enough for orientation and one-time conversions, but it does not perform datum shifts. If you're feeding GNSource antennas into a static-baseline geodetic network, you'll already be using software that handles your local-datum transforms (PAGES, Bernese, RTKLIB, OPUS) — use that for final coordinates. This tool is for quick visualisation and format swapping, not survey deliverables.
Need a high-precision GNSS antenna?
Coordinate-grade work needs phase-stable antennas — not just GNSS chips. Browse our 3D choke ring, multi-frequency survey, and CORS-grade product lines, or send your accuracy requirement and we'll spec a fit.