What a photo's metadata reveals about you

Open a photo and you see a picture. The file holds more. Wrapped around the pixels are labeled blocks of notes written by your camera and by any app that touched the photo afterward. Most of it is harmless on its own. Some of it is not, and it travels with the file unless something removes it.

The three kinds of notes

Photo metadata comes in a few standard formats, and one photo can hold several at once.

• EXIF is written by the camera. It is the main one.
• XMP is a more flexible format that editing apps often add, sometimes repeating details that EXIF already holds.
• IPTC is built for publishing: captions, credits, keywords and copyright notes. News and stock photos use it a lot. Phone photos rarely do, unless an editing app added it.

What can be inside

What you actually find depends on the device, its settings and what has happened to the file since. These are the things that can often turn up.

Where

If location tagging was on when you took the photo, the file can hold latitude and longitude, and sometimes altitude and the direction the camera faced. Coordinates from a phone are often accurate to a few meters. That is the difference between “somewhere in this neighborhood” and “this front door.”

When

Cameras record the date and time to the second, and some record the time zone offset as well. A time stamp tells people when you were at a place, and when you were not.

What took it

The maker and model of the device are usually there. Some cameras add a serial number, a lens name or an owner name. A serial number can tie photos from different places to one device.

How it was edited

Editing apps often write their name, the version and a list of steps taken. That can include a note that a photo was cropped, or the original file name.

A preview that outlives a crop

Many photos contain a small preview image of the whole shot, used for quick display. Some editors update it when you crop or paint over part of the picture, and some do not. When they do not, the preview can still show the part you removed.

Data after the picture

A photo file can carry extra data stored after the image itself. Some phones attach a short video clip or a depth map this way, and some editing apps tuck a second copy of the picture there. Software that only reads the visible picture will not show it.

What many photos say together

One photo with a location is one data point. A folder of them is a pattern. Time stamps and coordinates across weeks can often show:

• the place you sleep, where photos cluster at night
• where you work, and when you commute
• the gym, school or friend’s house you visit on a schedule
• the days you are away from home

None of this needs special skill. It needs a pile of photos with the notes still attached. That is the reason to be careful with an album shared in bulk, such as a folder of listing photos or a whole trip.

Don’t overstate it

Metadata is not always there. Location tagging can be off, many apps remove metadata on upload, and a screenshot usually has less than a camera photo. A photo with no location can still be traced by what it shows. A mailbox number or a distinctive skyline gives the place away without any notes. Metadata is one leak among several, and the easiest one to close.

How to look at your own photos

Check a photo before you share it. The metadata remover lists every block it finds in each JPEG, PNG or WebP photo you choose: location, device, dates, software and extra metadata blocks. It works in your browser, so the photo is not uploaded. You can look at the list and decide, or download a clean copy with the notes removed and the picture left exactly as it was.

To stop new photos from recording a location at the source, see how to remove location from photos on iPhone and Android. To learn how a photo behaves once you send it, read does sending a photo keep its location?