Tunisia Lambert: convert GPS to North and South Lambert
Tunisia uses two Lambert conformal conic zones on the Carthage datum (Clarke 1880 ellipsoid): North Tunisia (EPSG:22391, parallel 36° N) and South Tunisia (EPSG:22392, parallel 33°18′ N), both on the 9°54′ E meridian. The whole country also fits in UTM zone 32 N. The converter goes from GPS (WGS 84) to these systems and back, applying the datum shift many tools forget.
- EPSG:22391
- EPSG:22392
- UTM 32–32 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.
Which zone for which region?
Carte suggests Lambert North north of 34°39′ N (38.5 grads) — Tunis, Bizerte, Beja, Sousse, Kairouan, Sfax — and Lambert South beyond — Gafsa, Tozeur, Gabes, Djerba, Medenine, Tataouine. In UTM, all of Tunisia is in zone 32 N, from 6° E to 12° E. The zone written on the plan always prevails.
Projection parameters
The EPSG registry values — the ones the converter, Carte and MawCAD use.
| System · Projection | EPSG | Latitude of origin | Central meridian | Scale factor k₀ | False origin X₀ / Y₀ | Suggested latitudes |
|---|---|---|---|---|---|---|
| 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 |
Datum and the shift to WGS 84
The Carthage–WGS 84 step uses transformation EPSG:1130 (Carthage to WGS 84 (1): a shift of −263 m, 6 m and 431 m), stated to about 14 m for mainland Tunisia. A tool that ignores this datum shift moves points by 170 to 190 m: the most common mistake with Tunisian Lambert, the one behind points that “miss” on the satellite imagery.
| Datum | Ellipsoid | a / 1/f | Transformation to WGS 84 | Stated accuracy |
|---|---|---|---|---|
| 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 |
| WGS 84 | WGS 84 | 6,378,137.000 m / 298.257223563 | none | — |
Coordinates of the main cities
Approximate city centre. X and Y in metres, computed with the same definitions as the converter.
| City | Lat., long. (WGS 84) | National Lambert | UTM (WGS 84) | Map |
|---|---|---|---|---|
| Tunis | 36.806510.1815 | TN X 525,062.21Y 389,332.45 | 32NE 605,393.14N 4,074,058.22 | Map |
| Ariana | 36.866510.1647 | TN X 523,545.37Y 395,984.95 | 32NE 603,813.34N 4,080,696.04 | Map |
| Bizerte | 37.27449.8739 | TN X 497,634.33Y 441,212.85 | 32NE 577,476.69N 4,125,671.02 | Map |
| Nabeul | 36.456110.7376 | TN X 575,006.50Y 350,746.44 | 32NE 655,706.10N 4,035,941.73 | Map |
| Beja | 36.72569.1817 | TN X 435,801.89Y 380,557.30 | 32NE 516,224.87N 4,064,448.38 | Map |
| Jendouba | 36.50118.7802 | TN X 399,661.58Y 355,991.88 | 32NE 480,316.02N 4,039,552.56 | Map |
| El Kef | 36.18228.7147 | TN X 393,365.66Y 320,689.39 | 32NE 474,345.83N 4,004,195.11 | Map |
| Sousse | 35.825610.6084 | TN X 563,937.31Y 280,720.41 | 32NE 645,285.83N 3,965,799.01 | Map |
| Monastir | 35.764310.8113 | TN X 582,327.97Y 274,073.88 | 32NE 663,741.27N 3,959,319.36 | Map |
| Kairouan | 35.678110.0963 | TN X 517,713.38Y 264,145.88 | 32NE 599,208.85N 3,948,799.60 | Map |
| Kasserine | 35.16768.8365 | TN X 403,089.81Y 208,035.11 | 32NE 485,110.83N 3,891,641.76 | Map |
| Sfax | 34.740610.7603 | TN X 578,719.90Y 160,492.58 | 32NE 661,144.52N 3,845,688.12 | Map |
| Gafsa | 34.42508.7842 | TS X 397,402.28Y 425,113.46 | 32NE 480,171.12N 3,809,301.88 | Map |
| Tozeur | 33.91978.1335 | TS X 336,656.46Y 369,910.71 | 32NE 419,904.23N 3,753,590.52 | Map |
| Gabes | 33.881510.0982 | TS X 518,279.09Y 364,310.24 | 32NE 601,559.37N 3,749,559.69 | Map |
| Djerba (Houmt Souk) | 33.875610.8575 | TS X 588,506.52Y 364,044.88 | 32NE 671,797.23N 3,749,915.44 | Map |
| Medenine | 33.354910.5055 | TS X 556,286.05Y 306,068.65 | 32NE 640,078.21N 3,691,644.32 | Map |
| Tataouine | 32.929710.4518 | TS X 551,538.98Y 258,901.11 | 32NE 635,734.55N 3,644,428.47 | Map |
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 |
|---|---|---|---|---|
| 32N WGS 84 / UTM zone 32N | EPSG:32632 | 9° | 6° → 12° | Algeria · Tunisia · France |
Frequently asked questions
What is the EPSG code of Tunisia Lambert North?
EPSG:22391 (Carthage / Nord Tunisie); Tunisia Lambert South is EPSG:22392. UTM zone 32 N is EPSG:22332 on Carthage and EPSG:32632 on WGS 84.
Why are my Tunisian Lambert points about 200 m off on the satellite imagery?
Because the Carthage datum was not converted to WGS 84. Lambert X/Y refer to the Clarke 1880 ellipsoid; without transformation EPSG:1130, the gap reaches 170 to 190 m. The converter, Carte and MawCAD always apply it.
Tunisia Lambert North or South: which one?
The one of the latitude: Lambert North north of about 34°39′ N (Sfax included), Lambert South further south. The converter suggests it from the GPS position; if the existing plan is in the other zone, keep the plan's.
Are these coordinates valid for the land registry?
They are for locating and checking. For a land document or a boundary marking, turn to a licensed surveyor (géomètre-expert) or to the Office de la Topographie et du Cadastre (OTC).
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.