Convert projected coordinates in metres (Web Mercator or UTM easting/northing) back to decimal degrees latitude and longitude. Enter the X and Y, tell the tool which projection they are in, and read the WGS84 result, free and in your browser.
You cannot turn raw metres into degrees on their own. A value like 448265 is a distance east of some projection's origin, and it means a completely different place in Web Mercator than in a UTM zone. So the first step is always to know the source coordinate system. If the data came from a web map or a tile service, it is almost certainly Web Mercator (EPSG:3857). If it came from a survey, a national grid or engineering plans, it is more likely a UTM zone recorded in the file's metadata or its .prj sidecar.
Web Mercator coordinates X = 255989, Y = 6250779 reproject to about 48.858, 2.300 in decimal degrees (latitude, longitude), a point in Paris. Web Mercator values grow non-linearly with latitude, which is why the northing is far larger than the longitude suggests.
UTM zone 31N coordinates E = 448265, N = 5411932 reproject to roughly 48.858, 2.295 (latitude, longitude). Note the zone (31) and hemisphere (N) are essential: the same easting and northing in zone 32 or in the southern hemisphere would land somewhere entirely different.
Sydney sits at UTM zone 56S, E = 334519, N = 6251930, which reprojects to about -33.869, 151.209. The southern northing is large (over six million metres) because it is measured from a false origin at the South Pole, not the equator. Tick southern hemisphere before you convert, or the point comes out in the wrong half of the world.
| System | EPSG | Where you meet it |
|---|---|---|
| Web Mercator | 3857 | Google Maps, OpenStreetMap, Mapbox, web tiles |
| UTM (WGS84) | 326xx (N) / 327xx (S) | Surveying, engineering, drone and military data |
| WGS84 lat/long | 4326 | The degrees you are converting to, not metres |
A few well-known places in projected metres and the decimal degrees they reproject to, so you can sanity-check your own results against them.
| Place | System | Metres (X, Y) | Decimal degrees |
|---|---|---|---|
| London | Web Mercator | -14,226, 6,711,544 | 51.5074, -0.1278 |
| Paris | UTM 31N | 448,266, 5,411,932 | 48.8584, 2.2945 |
| New York | Web Mercator | -8,238,310, 4,970,072 | 40.7128, -74.0060 |
| Sydney | UTM 56S | 334,519, 6,251,930 | -33.869, 151.209 |
The whole conversion hinges on knowing which projection your metres are in, so it is worth a moment to find out rather than guess. A few reliable checks:
.prj file. Open it in a text editor: a name like WGS_1984_UTM_Zone_31N or an AUTHORITY["EPSG","32631"] tag tells you the exact system. EPSG 326xx is UTM north, 327xx is UTM south, and 3857 is Web Mercator.gdalsrsinfo or ogrinfo print it from the command line.If you genuinely cannot tell, try the most likely candidate, convert, and see whether the result lands where you expect on a map. A point that comes out in the ocean or at Null Island (0, 0) means the projection or the X/Y order is wrong.
Projected coordinates are already at ground scale, so precision is easy to reason about: one metre of easting or northing is one metre on the ground (within a UTM zone). That means the decimal places on your metres map almost directly to position, a whole metre is a whole metre, and tenths of a metre are centimetres. When the tool reprojects back to decimal degrees it gives six decimal places, which is about 11 cm of latitude, finer than most projected source data. In practice, five or six decimal places of output is plenty; adding more does not add real accuracy, it just reflects the maths. If your metres were only recorded to the nearest metre, do not read the degree output as if it were survey-grade.
Once you have decimal degrees you can map the point anywhere: paste it into a spreadsheet and use the spreadsheet to map converter, or view it in Google Earth via CSV to KML. To go the other direction, from latitude and longitude into projected metres, use latitude/longitude to UTM for the surveyor's grid or latitude/longitude to Web Mercator for web-map tiles. For everyday degree-to-degree work between DMS, DD and DDM, the full coordinate converter handles all three at once.
Not without knowing the projection. Metres are eastings and northings in a projected coordinate system, so you must say which one, Web Mercator (EPSG:3857) or a specific UTM zone, before they can be turned back into longitude and latitude degrees.
Web Mercator values are usually large and can be negative (for example X = -8,238,310). UTM eastings sit between roughly 160,000 and 834,000 and northings are 0 to 10,000,000, always positive, with a separate zone number. If a file came from a web map or tile scheme it is almost always Web Mercator (EPSG:3857).
The easting is the X value (metres east of the projection origin) and the northing is the Y value (metres north). Enter X in the first box and Y in the second. Swapping them puts the point in the wrong place, the same trap as swapping latitude and longitude.
Use the zone the data was created in, it is usually recorded in the file's metadata or .prj. Each zone is six degrees of longitude wide. Also tick 'southern hemisphere' for data below the equator, because northings there are measured from a false origin.
No. The reprojection runs in your browser with proj4, the same library desktop GIS uses. Your coordinates never leave your device and it works offline once loaded.
WGS84 latitude and longitude is EPSG:4326. That is what this tool converts your projected metres into: plain longitude/latitude degrees you can use in Google Earth, GeoJSON or any web map.
This tool reprojects one X/Y pair at a time. For a whole list, convert the file itself instead: load a projected CSV into the spreadsheet to map tool and set its coordinate system, and every row is reprojected together.