WGS84 to Web Mercator Converter

Convert WGS84 to Web Mercator

Web Mercator (EPSG:3857) is the projection used by almost every web mapping library — Google Maps, OpenStreetMap, Leaflet, and Mapbox — for fast interactive tile rendering. This converter transforms WGS84 latitude/longitude coordinates (EPSG:4326) to Web Mercator metres and back for use in custom cartographic applications and GIS pipelines.

Source file

Drop an Excel file or browse

.xlsx · first row used as headers · max 25 MB

Identify coordinate columns

X / Easting columnY / Northing column

Coordinate reference systems

Source CRSTarget CRS

Sourcefrom

WGS 84 (longitude / latitude)

EPSG:4326

units: degrees · geographic

Targetto

Web Mercator

EPSG:3857

units: meters · projected

Transform & export

About this conversion

Web Mercator projects the earth onto a square using a spherical approximation of WGS84. The result is a coordinate system in metres suitable for fast tile rendering, at the cost of extreme area distortion toward the poles — Greenland ends up looking larger than Africa. For measuring distances or areas, Web Mercator is wrong; for rendering interactive maps, it is the de facto standard.

Developers commonly need this conversion when their data is in lat/lon but a mapping library or vector tile service expects metres, or when exported map features come back in EPSG:3857 and need to be joined with GPS data in lat/lon. GeoTransform handles both directions from the same page — the converter's default is WGS84 → Web Mercator, and the swap button reverses it.

For small-area work near the equator, Web Mercator is close enough to a true metric projection for rough distance calculations. Anywhere else, use UTM or a local projected CRS instead.

Frequently Asked Questions

Is Web Mercator the same as Google's projection?

Yes. Google Maps, Bing Maps, OpenStreetMap, and almost every slippy-map tile service use Web Mercator (EPSG:3857, also sometimes labelled EPSG:900913). The projection and coordinate values are identical across all of these platforms.

Why does Web Mercator distort so much near the poles?

The projection stretches vertical distances to preserve local angles (conformality), which is what makes rotation and zooming on a web map look correct. The tradeoff is that land near the poles is inflated dramatically — a known but accepted tradeoff for interactive web cartography.

Can I use Web Mercator metres for distance measurements?

Only very approximately, and only near the equator. At typical Norwegian latitudes, Web Mercator distances are overstated by a factor of roughly 2. For real distance or area calculations, reproject to UTM or a geographic calculation instead.