GPS, Lambert and UTM coordinate converter
Type a WGS 84 latitude and longitude: the X/Y appear in the chosen system — and the other way round. 32 coordinate systems for Morocco, Algeria, Tunisia and France, with the parameters and datum transformations of the EPSG registry.
- EPSG:26191
- EPSG:26192
- EPSG:26194
- EPSG:26195
- EPSG:30791
- EPSG:30792
- EPSG:22391
- EPSG:22392
- EPSG:2154
- UTM 28–32 N
- Computed in your browser: no coordinate is sent or stored, and no account is needed.
- Definitions checked against the EPSG registry with PROJ: less than a millimetre apart on all 32 systems.
Coordinate converter
Edit either side, the other follows.
For this point:
Batch conversion
One point per line: a name, then X and Y (or latitude and longitude), and Z if you have it. Separators: semicolon, tab, comma or space.
One guide per country
Projection and datum: the two steps of a conversion
A GPS position is a latitude and a longitude on the WGS 84 ellipsoid. National plans are in X/Y: each country projects its own ellipsoid — Clarke 1880 for Merchich, Nord Sahara 1959 and Carthage, GRS 80 for RGF93 — onto a cone (the Lambert projection) or a cylinder (UTM). Converting therefore means shifting the datum and then projecting, or the reverse. Forgetting the datum shift moves points by 70 m in Algeria to more than 300 m in Morocco; picking the wrong zone sends them tens of kilometres away.
Projection parameters
The EPSG registry values — the ones the converter, Carte and MawCAD use.
| System · Projection | EPSG | Latitude of origin | Central meridian | Standard parallels | Scale factor k₀ | False origin X₀ / Y₀ | Suggested latitudes |
|---|---|---|---|---|---|---|---|
| N Morocco Lambert North (zone 1)Merchich / Nord MarocLambert conformal conic, 1 parallel | EPSG:26191 | 33.3° (37 gr) | −5.4° (−6 gr) | — | 0.999625769 | 500,000 / 300,000 | north of 31°30′ N |
| S Morocco Lambert South (zone 2)Merchich / Sud MarocLambert conformal conic, 1 parallel | EPSG:26192 | 29.7° (33 gr) | −5.4° (−6 gr) | — | 0.999615596 | 500,000 / 300,000 | 27°54′ – 31°30′ N |
| SN Morocco Lambert Sahara North (zone 3)Merchich / Sahara NordLambert conformal conic, 1 parallel | EPSG:26194 | 26.1° (29 gr) | −5.4° (−6 gr) | — | 0.999616304 | 1,200,000 / 400,000 | 24°18′ – 27°54′ N |
| SS Morocco Lambert Sahara South (zone 4)Merchich / Sahara SudLambert conformal conic, 1 parallel | EPSG:26195 | 22.5° (25 gr) | −5.4° (−6 gr) | — | 0.999616437 | 1,500,000 / 400,000 | south of 24°18′ N |
| AN Algeria Lambert NorthNord Sahara 1959 / Nord AlgerieLambert conformal conic, 1 parallel | EPSG:30791 | 36° (40 gr) | 2.7° (3 gr) | — | 0.999625544 | 500,135 / 300,090 | north of 34°39′ N |
| AS Algeria Lambert SouthNord Sahara 1959 / Sud AlgerieLambert conformal conic, 1 parallel | EPSG:30792 | 33.3° (37 gr) | 2.7° (3 gr) | — | 0.999625769 | 500,135 / 300,090 | 31°57′ – 34°39′ N |
| TN Tunisia Lambert NorthCarthage / Nord TunisieLambert conformal conic, 1 parallel | EPSG:22391 | 36° (40 gr) | 9.9° (11 gr) | — | 0.999625544 | 500,000 / 300,000 | north of 34°39′ N |
| TS Tunisia Lambert SouthCarthage / Sud TunisieLambert conformal conic, 1 parallel | EPSG:22392 | 33.3° (37 gr) | 9.9° (11 gr) | — | 0.999625769 | 500,000 / 300,000 | south of 34°39′ N |
| L93 Lambert-93RGF93 v1 / Lambert-93Lambert conformal conic, 2 parallels | EPSG:2154 | 46.5° | 3° | 44° · 49° | — | 700,000 / 6,600,000 | — |
Datum and the shift to WGS 84
| Datum | Ellipsoid | a / 1/f | Transformation to WGS 84 | Stated accuracy |
|---|---|---|---|---|
| Merchich | Clarke 1880 (IGN) | 6,378,249.200 m / 293.466021294 | Merchich to WGS 84 (1) (EPSG:1166) ΔX ΔY ΔZ = 31 · 146 · 47 m | ± 7 m |
| Nord Sahara 1959 | Clarke 1880 (RGS) | 6,378,249.145 m / 293.465 | Nord Sahara 1959 to WGS 84 (11) (EPSG:10296) ΔX ΔY ΔZ = −267.407 · −47.068 · 446.357 m Rx Ry Rz = −0.179423 · 5.577661 · −1.27762″ · ds = 1.204866 ppm | ± 1 m |
| Carthage | Clarke 1880 (IGN) | 6,378,249.200 m / 293.466021294 | Carthage to WGS 84 (1) (EPSG:1130) ΔX ΔY ΔZ = −263 · 6 · 431 m | ± 14 m |
| RGF93 v1 | GRS 1980 | 6,378,137.000 m / 298.257222101 | RGF93 v1 to WGS 84 (1) (EPSG:1671) | ± 1 m |
| WGS 84 | WGS 84 | 6,378,137.000 m / 298.257223563 | none | — |
UTM zones
UTM cuts the globe into 6° zones of longitude, all on WGS 84: scale factor 0.9996 on the central meridian, X₀ = 500,000 m, Y₀ = 0 north of the equator. Zones 28 to 32 N cover Morocco, Algeria, Tunisia and France; a point's zone follows from its longitude.
| Zone | EPSG | Central meridian | Longitudes | Countries |
|---|---|---|---|---|
| 28N WGS 84 / UTM zone 28N | EPSG:32628 | −15° | −18° → −12° | Morocco |
| 29N WGS 84 / UTM zone 29N | EPSG:32629 | −9° | −12° → −6° | Morocco · Algeria |
| 30N WGS 84 / UTM zone 30N | EPSG:32630 | −3° | −6° → 0° | Morocco · Algeria · France |
| 31N WGS 84 / UTM zone 31N | EPSG:32631 | 3° | 0° → 6° | Algeria · France |
| 32N WGS 84 / UTM zone 32N | EPSG:32632 | 9° | 6° → 12° | Algeria · Tunisia · France |
Frequently asked questions
What is a Lambert projection?
A conformal conic projection: it unrolls the ellipsoid onto a tangent or secant cone, which preserves angles and gives plane X/Y coordinates in metres. Each country tunes it to its latitude: four zones in Morocco, two in Algeria and in Tunisia, Lambert-93 and nine CC zones in France.
What is the difference between WGS 84, Lambert and UTM?
WGS 84 gives a position in degrees (latitude, longitude): the one from your GPS, your phone or Google Maps. Lambert and UTM give X/Y in metres on a plan: Lambert in a country's national system, UTM in a worldwide 6° zone of longitude. The converter goes from one to the other.
How do I enter degrees, minutes and seconds?
Type them as they are: 33°34'23"N, 33 34 23 N or 33.5731 — with W, S or a minus sign for west and south. A decimal comma works too (33,5731). The result is also shown in degrees, minutes and seconds.
Are my coordinates sent anywhere?
No. The computation runs in your browser with the proj4js library and the EPSG definitions: no coordinate is sent to the server or stored. The converter works without an account.
Can I use the results in AutoCAD, Covadis or QGIS?
Yes. Copy X and Y — tab separated, they paste into two columns — or download the CSV of a batch conversion. To draw, Carte exports DXF, Shapefile with .prj, KML and GeoJSON, and MawCAD takes the survey into CAD with a free account.
Can I convert a list of points at once?
Yes: open “Batch conversion”, paste your points — one per line, with a name, the two coordinates and Z if you have it — then download the result as CSV or copy it into a spreadsheet. Nothing is sent: everything is computed in the browser.
Survey in this zone
Carte opens the satellite imagery straight in the chosen zone: points, lines and areas with live X/Y, export to DXF, Shapefile (with .prj) or KML. With a free account, the survey moves on to MawCAD for CAD drafting.