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Image AnalysisBeginner6 min read

How to Use EXIF Data Clues

Extract GPS coordinates, timestamps, camera settings, and hidden information from image metadata. A common technique in geocaching puzzle caches.

What is EXIF Data?

EXIF (Exchangeable Image File Format) is metadata embedded in photos by cameras and smartphones. This includes camera settings, timestamps, and crucially for geocachers — GPS coordinates of where the photo was taken.

Puzzle cache owners often hide clues in EXIF data, either directly (coordinates in the GPS field) or indirectly (encoded in comments, camera serial numbers, or timestamps).

GPS Coordinates in EXIF

Direct Coordinate Extraction

Most smartphones record GPS location when taking photos. Puzzle setters may:

  • Take a photo at the cache location or a waypoint
  • Provide a "hint photo" with embedded coordinates
  • Use the GPS altitude field for part of the puzzle

Typical EXIF GPS fields:

GPS Latitude: N 51° 30' 26.4"
GPS Longitude: W 0° 7' 39.6"
GPS Altitude: 12.3 meters
GPS Timestamp: 14:35:22

Use our Coordinate Converter to convert the DMS format to decimal degrees or your preferred format.

Important: Some puzzle setters strip GPS data but leave other clues. Always check ALL EXIF fields, not just GPS.

How to Extract EXIF Data

Online Tools

  • Jeffrey's EXIF Viewer — Comprehensive online tool
  • ExifData.com — Simple drag-and-drop interface
  • Pic2Map — Shows GPS location on a map

Desktop Methods

  • Windows: Right-click → Properties → Details tab
  • Mac: Preview → Tools → Show Inspector (Cmd+I)
  • ExifTool: Command-line tool for complete extraction

ExifTool command (most thorough):

exiftool -a -u -g1 image.jpg

-a shows all tags, -u shows unknown tags, -g1 groups output

Hidden Clues in EXIF Fields

Common Hiding Places

Comment / User Comment

Free text field — can contain ciphertext, coordinates, or hints

Example: "N52.12345 W001.67890"

Image Description / Title

Often overlooked — may contain encoded messages

Artist / Copyright

Can be edited to contain clues

Camera Serial Number

Numeric — could be A1Z26 encoded or contain coordinate digits

Example: "5212345" = 52.12345°

Software / Processing Software

May contain unusual values that are actually clues

Timestamp Tricks

Dates and times can encode numbers:

  • Date: 2023-05-21 → coordinates could be 52.321 or similar
  • Time: 14:35:22 → 143522 could be part of coordinates
  • Modified vs Original timestamps might differ intentionally

Camera Settings as Clues

Technical camera settings are less commonly used but can hide numbers:

ISO Speed

Usually 100-6400

ISO 5234 → 52.34?

Focal Length

Usually 18-200mm

52mm focal → N52°?

Shutter Speed

Expressed as fractions

1/125 → 125

F-Number (Aperture)

Usually f/1.4 to f/22

f/5.6 → 56

Image Dimensions

Width × Height in pixels

5234 × 1234 pixels

Solving Tip: If camera settings seem unusual (ISO 5234 instead of standard values like 100, 200, 400, 800), they're likely intentional puzzle clues.

Beyond EXIF: XMP & IPTC

Images can contain multiple types of metadata beyond EXIF:

XMP (Extensible Metadata Platform)

Adobe's XML-based format — can store extensive custom data

  • Keywords and tags
  • Rating and labels
  • Custom fields

IPTC (International Press Telecommunications Council)

Journalist/publisher metadata — many text fields available

  • Caption / Description
  • Location fields (City, State, Country)
  • Credit and Source

EXIF Analysis Checklist

  1. Download the original image — right-click and save, don't screenshot
  2. Check GPS coordinates first — most direct clue
  3. Read ALL text fields — Comments, Description, Artist, Copyright
  4. Note unusual numeric values — ISO, serial numbers, dimensions
  5. Check timestamps — Date/time might encode coordinates
  6. Compare multiple images — if puzzle has several, differences matter
  7. Use ExifTool for complete extraction — shows fields GUIs miss
  8. Check XMP and IPTC — additional metadata standards

Common Pitfalls

  • Screenshots strip EXIF. Always download the original image file. Taking a screenshot removes all metadata.
  • Social media strips EXIF. Images uploaded to Facebook, Twitter, Instagram, etc. have EXIF removed. Look for original file links.
  • Geocaching.com resizes images. The thumbnail may lose data — look for "View Original" or full-size image links.
  • GPS coordinates may be approximate. Phone GPS accuracy varies — the coordinates might point to nearby, not exact location.