How It Works

From image to verified GPS metadata

GM GeoTag is designed around local browser processing. The browser reads the image, the map helps you choose coordinates, and JPEG EXIF is generated and read again before success is reported.

01 · UPLOAD

Choose an image

Files are checked for supported image MIME types, size and whether the browser can decode them.

02 · READ

Inspect EXIF

Available EXIF fields are parsed. If GPS exists, DMS values are converted to decimal coordinates.

03 · SET

Choose a location

Use the map, marker, manual coordinates, place search or explicitly requested browser location access.

04 · VERIFY

Write and re-read

JPEG GPS EXIF is written, the generated file is parsed again, and the requested coordinates are compared before download.

Maps and place search

Maps use Leaflet with OpenStreetMap tiles. Place search uses the OpenStreetMap/Nominatim ecosystem. Search requests are debounced to avoid unnecessary calls. External services have their own usage rules and policies.

Why JPEG matters

JPEG has a well-established EXIF structure and is the primary output format for embedded GPS metadata in this implementation. PNG and WebP are not labelled as having standard GPS EXIF embedded when this browser implementation cannot guarantee that result.

What happens to your image?

Core processing is designed to occur in your browser. The site does not intentionally upload your image to its own server for the core tools. Map tiles and place-search requests are external network requests, described on the Privacy page.