EPSG:27700 OSGB36 / British National Grid
Projected system (Transverse Mercator) in use: UK - Britain and UKCS 49°45'N to 61°N, 9°W to 2°E. The full definition below, and conversion in one click.
| Code | EPSG:27700 |
|---|---|
| Name | OSGB36 / British National Grid |
| Type | Projected system — Transverse Mercator |
| Area of use |
UK - Britain and UKCS 49°45'N to 61°N, 9°W to 2°E United Kingdom (UK) - offshore to boundary of UKCS within 49°45'N to 61°N and 9°W to 2°E; onshore Great Britain (England, Wales and Scotland). Isle of Man onshore. |
| Bounds | W -9,01° · S 49,75° · E 2,01° · N 61,01° |
| Countries | United Kingdom |
| Datum | Ordnance Survey of Great Britain 1936 |
| Ellipsoid | Airy 1830 a = 6377563.396 m · 1/f = 299.3249646 |
| Base geographic system | EPSG:4277 — OSGB36 |
| Unit | metre (E east, N north) |
| Transformation to WGS 84 | OSGB36 to WGS 84 (6) (EPSG:1314) — accuracy 2 m |
| Scope | Engineering survey, topographic mapping. |
Projection parameters
| Parameter | Value | Unit |
|---|---|---|
| Latitude of natural origin | 49 | degree |
| Longitude of natural origin | -2 | degree |
| Scale factor at natural origin | 0.9996012717 | unity |
| False easting | 400000 | metre |
| False northing | -100000 | metre |
proj4 definition
+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +a=6377563.3959999997 +rf=299.3249646 +units=m +towgs84=446.448,-125.157,542.06,0.15,0.247,0.842,-20.489 +no_defsPaste it into QGIS, proj4js, PostGIS (spatial_ref_sys) or GDAL. +towgs84 carries the EPSG transformation to WGS 84; the official code stays EPSG:27700.
WKT (ESRI format, the .prj content)
PROJCS["British_National_Grid",GEOGCS["GCS_OSGB_1936",DATUM["D_OSGB_1936",SPHEROID["Airy_1830",6377563.396,299.3249646]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",400000.0],PARAMETER["False_Northing",-100000.0],PARAMETER["Central_Meridian",-2.0],PARAMETER["Scale_Factor",0.9996012717],PARAMETER["Latitude_Of_Origin",49.0],UNIT["Meter",1.0]]Other systems — United Kingdom
- EPSG:10235OxWo08 Grid
- EPSG:10237SYC20-IRF
- EPSG:10240SYC20 Grid
- EPSG:10272SMITB20-IRF
- EPSG:10275SMITB20 Grid
- EPSG:10277RBEPP12-IRF
- EPSG:10280RBEPP12 Grid
- EPSG:10468COV23-IRF
- EPSG:10471COV23 Grid
- EPSG:10623ECML14-IRF
- EPSG:10626ECML14 Grid
- EPSG:10628WC05-IRF
- EPSG:10632WC05 Grid
- EPSG:20002MWC18 Grid
- EPSG:20033MWC18-IRF
- EPSG:23090ED50 / TM 0 N
- EPSG:29901OSNI 1952 / Irish National Grid
- EPSG:29903TM75 / Irish Grid
Source: EPSG registry v11.022 (IOGP), through the PROJ database. Always check a code on epsg.org before contractual work.