EXIF (Exchangeable Image File Format) is a block of metadata that cameras write into a photo file alongside the pixel data — camera model, exposure settings, timestamp, and, when location services are on, GPS coordinates. It's invisible when you look at the photo, but it's exactly what maps apps, Photos libraries, and GIS software read to know where a picture was taken.
What's actually inside GPS EXIF
The GPS block of an EXIF tag (formally GPSInfoIFD) can hold latitude, longitude, altitude, a GPS timestamp, and sometimes heading and accuracy — though most default camera apps only populate latitude, longitude and altitude. It's stored as structured data, not text, so it survives resizing and most edits, but it doesn't survive every step of a file's journey.
How to check if a photo has GPS EXIF
- On iPhone: open the photo in Photos, tap the info (ⓘ) button — a map appears if location data is present.
- On Android: open the photo in Google Photos and tap the info icon; a map thumbnail indicates GPS data.
- On desktop: right-click → Get Info (Mac) or Properties → Details (Windows), or use a dedicated EXIF viewer for full metadata.
- Command line:
exiftool photo.jpglists every EXIF field, GPS included, for anyone comfortable with a terminal.
Where GPS EXIF quietly disappears
This is the part that catches people off guard: a photo can look completely normal and still have lost its location data along the way.
- Messaging apps — WhatsApp, and many others strip EXIF from images sent through chat by default, for user privacy.
- Screenshots — a screenshot of a photo is a brand-new image with none of the original's metadata.
- Some social platforms — strip location (and often other EXIF) on upload, again for privacy reasons.
- Certain editing/export steps — "Save for web" and some compression tools drop metadata to save file size.
None of this is a bug — it's usually intentional privacy protection for casual users. But if the photo is the record — a site inspection, a completed-work sign-off for surveyors and engineers — losing that metadata silently is a real problem.
Why a visible stamp is the more durable record
A stamp burned into the image itself — coordinates, date, address printed directly on the pixels — survives every one of the scenarios above, because it's not metadata anyone can strip; it's part of the picture. The strongest approach uses both: GPS EXIF for software that reads it automatically, and a visible stamp for the moment a human looks at the photo without any tool at all — printed, screenshotted, or forwarded through an app that strips metadata.
| Scenario | GPS EXIF alone | Visible stamp |
|---|---|---|
| Opened in GIS software | Reads automatically | Visible but not auto-parsed |
| Forwarded via WhatsApp | Usually stripped | Survives (it's in the pixels) |
| Printed for a physical file | Invisible | Readable |
| Screenshotted | Lost | Survives |
Terramark writes full GPS EXIF into every photo — stamped and raw — while also burning coordinates, date, address, altitude and accuracy directly onto the stamped image. Belt and suspenders, on purpose.
Read the geotagging guideIf you're building photos into a formal inspection or audit trail, proof-of-work photos for field inspections covers what else a defensible record needs beyond location data.