GPS EXIF Tags Explained: What Each Location Field Means
October 31, 2026
GPS EXIF tags are a set of location fields stored inside a photo file. The core ones are GPSLatitude, GPSLongitude and their N/S and E/W reference tags. Optional tags can add altitude, compass direction, a UTC timestamp, speed and the positioning method. Together they tell software where the photo was taken.
Where do GPS tags live inside a photo file?
GPS tags sit in their own block of EXIF called the GPS IFD (image file directory). The main EXIF header holds a single pointer, tag 0x8825 (GPSInfo), that tells software where this block starts.
That separation matters. A photo can have a full set of camera settings and no GPS block at all. It can also have a GPS block with only a few fields filled in. If you have read our guide to EXIF data and how to read it, this is the location section of that same structure.
Every GPS tag has a name, a numeric ID, and a data type. Tools usually show you the name. The ID and type only matter if you are writing code or debugging a file that won't read properly.
What are the main GPS EXIF tags?
Most photos with location data use a handful of tags. The table below covers the ones you will see most often, based on the EXIF specification.
| Tag name | ID | Type | What it stores |
|---|---|---|---|
| GPSVersionID | 0x0000 | 4 bytes | Version of the GPS block, often 2.2.0.0 |
| GPSLatitudeRef | 0x0001 | Text | N or S |
| GPSLatitude | 0x0002 | 3 rationals | Degrees, minutes, seconds |
| GPSLongitudeRef | 0x0003 | Text | E or W |
| GPSLongitude | 0x0004 | 3 rationals | Degrees, minutes, seconds |
| GPSAltitudeRef | 0x0005 | 1 byte | 0 above sea level, 1 below |
| GPSAltitude | 0x0006 | 1 rational | Height in metres |
| GPSTimeStamp | 0x0007 | 3 rationals | Hour, minute, second in UTC |
| GPSSatellites | 0x0008 | Text | Satellite information, free-form |
| GPSMeasureMode | 0x000A | Text | 2 (2D fix) or 3 (3D fix) |
| GPSDOP | 0x000B | 1 rational | Dilution of precision (lower is better) |
| GPSSpeedRef / GPSSpeed | 0x000C / 0x000D | Text / rational | Unit (K, M, N) and speed |
| GPSImgDirectionRef / GPSImgDirection | 0x0010 / 0x0011 | Text / rational | T (true) or M (magnetic) north, and the bearing the camera faced |
| GPSMapDatum | 0x0012 | Text | Coordinate system, usually WGS-84 |
| GPSProcessingMethod | 0x001B | Undefined | How the position was found, such as GPS or NETWORK |
| GPSDateStamp | 0x001D | Text | Date in UTC, as YYYY:MM:DD |
| GPSHPositioningError | 0x001F | 1 rational | Estimated horizontal error in metres |
The specification also defines destination tags (the location the camera was pointing toward) and a few others. Cameras and phones rarely fill those in.
How are latitude and longitude actually stored?
Latitude and longitude are each stored as three fractions: degrees, minutes and seconds. A separate letter tag gives the hemisphere. The file does not store a minus sign.
Take a point in central London:
- GPSLatitudeRef:
N - GPSLatitude: 51/1, 30/1, 26/1
- GPSLongitudeRef:
W - GPSLongitude: 0/1, 7/1, 39/1
A reader converts that to decimal as degrees + minutes/60 + seconds/3600. That gives about 51.50722 and, because the reference is W, -0.12750.
The "rational" type is just a numerator and denominator. Phones often use a large denominator on the seconds for precision, such as 26123/1000 for 26.123 seconds. Some devices instead store decimal minutes and leave seconds at 0/1. Both are valid.
For the difference between decimal and DMS notation, see our latitude and longitude formats guide. Use it if you are copying coordinates from a map into a tool.
Why do the reference tags matter so much?
The reference tags decide which side of the equator and prime meridian the point is on. If they are wrong or missing, the photo lands in the wrong place.
The most common failure is a sign mismatch. Someone types -0.1275 into a field that expects a positive number plus W, or a script writes the right numbers with E instead of W. The photo then maps to the mirror-image location, often thousands of miles away. A photo that appears in the ocean or in the wrong hemisphere usually has this problem.
Altitude works the same way. GPSAltitude is always a positive number, and GPSAltitudeRef says whether it is above (0) or below (1) sea level.
What do the time and date tags record?
GPSTimeStamp and GPSDateStamp record when the position fix was taken, in UTC. They are separate from the camera's DateTimeOriginal tag, which is normally local time with no time zone attached.
This is useful if you match photos to a GPS track. The track log is in UTC, and the photo's clock is usually local time, so a mismatch of several hours is common. The GPS timestamp, when present, is a reliable reference point. Not every device writes it, and a camera with a wrong clock will write a wrong timestamp.
If your problem is the capture time rather than location, our post on fixing the wrong date taken covers it.
Which tags tell you how accurate the location is?
Three tags hint at accuracy: GPSDOP, GPSHPositioningError and GPSProcessingMethod. None of them is guaranteed to be present.
- GPSDOP is a unitless number. Lower values mean the satellite geometry was better.
- GPSHPositioningError gives an estimated error radius in metres. It is a newer addition to the standard, so older software and devices may not write or display it.
- GPSProcessingMethod may show whether the fix came from satellites, a network, or manual entry, but the wording is not standardised.
Most phone photos have none of these filled in clearly. Treat the coordinates as approximate. Our article on how accurate phone GPS is in photos goes into real-world expectations.
Do GPS tags exist outside EXIF too?
Yes. The XMP metadata format has its own versions of these fields, under the exif: namespace, such as exif:GPSLatitude. XMP stores coordinates as text, in a format like 51,30.4333N, rather than as three fractions.
Some software reads XMP and ignores EXIF, or the reverse. When both are present and disagree, results vary by program. A well-behaved tool keeps them in sync. If you see two different locations in two different apps, this is one possible cause. IPTC and XMP also carry text fields such as title, description and keywords, which EXIF does not handle well.
Which GPS tags do you need to write for a geotag to work?
For a basic geotag, you need latitude, longitude and their two reference tags. Everything else is optional.
Altitude, direction and timestamps add detail, but most apps that display a photo on a map only look at the core four. If you are adding a location to photos that have none, that is the set to get right.
When you use the Geotagr editor, you pick a point and the tool writes the GPS coordinates into the file, along with a title, description, keywords and business details if you add them. It runs in your browser, and the photo files are not uploaded to Geotagr's servers. HEIC, PNG and WebP files can be opened, but they are converted and saved as JPG.
How can you read the GPS tags in your own photos?
Open the photo in a metadata viewer and look for a GPS section. Our free photo metadata checker shows what is in a file, and the guide to checking photo metadata on any device covers built-in options on Windows, Mac, iPhone and Android.
Check for these things:
- Both reference tags are present and match the place you expect.
- Latitude and longitude values are plausible, not 0, 0.
- The timestamp is in UTC and close to the capture time.
- The tags are still there after you upload or share the file.
That last point catches many people. Some platforms strip metadata on upload, and Google has not published how it uses photo metadata. Having correct GPS tags does not promise any ranking or visibility benefit. See does geotagging help local SEO for what is known.
Frequently asked questions
What is the difference between GPS EXIF tags and a geotag?
A geotag is the general idea of attaching a location to a photo. GPS EXIF tags are one specific way to store it, in the GPS block of the file's EXIF data. Other places can also hold location, such as XMP fields or a separate sidecar file.
Which GPS EXIF tags are required?
The standard does not force any of them. In practice, software needs GPSLatitude, GPSLatitudeRef, GPSLongitude and GPSLongitudeRef to place a photo on a map. GPSVersionID is usually included as well, and the rest are optional.
Why does my photo show a location in the wrong country?
The most likely cause is a wrong reference letter, such as E where W should be, or coordinates with the wrong sign. Another cause is a camera or phone that saved a poor fix. Compare the values with the real place, then correct the location. Our guide to fixing the wrong location on a photo explains how.
Are GPS EXIF tags removed when I share a photo?
It depends on the app or platform. Some keep the metadata and some strip it, and the behaviour can change over time. To be sure, download the shared version and inspect it. If you want the location removed on purpose, follow our guide to removing location data from photos.
Is the altitude in GPS EXIF tags accurate?
Often not very. Altitude from a phone is usually less reliable than latitude and longitude, and it may be measured relative to sea level or an ellipsoid depending on the device. Use it as a rough figure only.
Can I edit GPS EXIF tags without special software?
Sometimes. Windows and macOS offer limited built-in options, and phone gallery apps can change location on existing photos. A browser-based tool lets you set coordinates for a whole batch. Our batch geotagging guide compares the methods.