Image metadata glossary
One page per field you will run into when you open a photo in an EXIF viewer. Each entry gives the tag name as ExifTool prints it, where the value lives in the file, what real values look like, and what tends to go wrong with it.
Entries that the EXIF editor can change say so at the top of the page. For the others, each page gives the ExifTool command.
Camera & lens
Which device took the picture. These fields identify a camera body, sometimes down to its serial number.
Camera make
EXIF:Make
What the EXIF Make tag stores, the exact strings Canon, Nikon, Sony and phones write, and why changing it can stop ExifTool decoding maker notes.
Camera model
EXIF:Model
The EXIF Model tag names the camera or phone that took a photo. Real values, why Canon repeats its brand, Sony's ILCE codes, and how to edit or strip it.
Lens model
EXIF:LensModel, EXIF:LensMake, EXIF:LensInfo
How EXIF records the lens: LensModel (0xA434), LensMake (0xA433) and LensInfo (0xA432), why ExifTool can print f/0, and where LensID comes from.
Maker notes
EXIF:MakerNoteCanon, EXIF:MakerNoteNikon, EXIF:MakerNoteSony
MakerNote (0x927C) is the vendor-specific EXIF block that holds lens IDs and shutter counts. Why edits corrupt it, and how ExifTool reads or strips it.
Serial number
EXIF:SerialNumber, EXIF:LensSerialNumber, XMP:SerialNumber
Camera and lens serial numbers sit in EXIF SerialNumber (0xA431), LensSerialNumber (0xA435), XMP and maker notes. Find every copy and remove them.
Software
EXIF:Software, EXIF:ProcessingSoftware, XMP:CreatorTool
EXIF Software (0x0131) names the app or firmware that last saved a photo. What iPhones and Lightroom write there, and where XMP repeats the same information.
Exposure
The settings behind the shot. Useful for learning from a reference photo, and stored as fractions or APEX values.
Aperture
EXIF:FNumber, EXIF:ApertureValue, EXIF:MaxApertureValue
How EXIF stores aperture: FNumber (0x829D) as a plain f-number, ApertureValue and MaxApertureValue in APEX units. The math, plus real ExifTool output.
Exposure compensation
EXIF:ExposureCompensation
ExposureCompensation, called ExposureBiasValue in the EXIF spec (tag 0x9204), records the EV shift dialed in. How it is stored and how ExifTool prints it.
Exposure mode
EXIF:ExposureMode
ExposureMode (0xA402) only says whether exposure was automatic, manual or auto-bracketed. Why it reads Auto in aperture priority, and how to change it.
Exposure program
EXIF:ExposureProgram
ExposureProgram (0x8822) records the shooting mode: Manual, Program AE, aperture or shutter priority, or a scene mode. Full value table and ExifTool output.
Flash
EXIF:Flash
The EXIF Flash tag (0x9209) packs five facts into one number: fired, strobe return, mode, function, red-eye. Decode 0x10, 0x18, 0x19 and 0x01 by hand.
Focal length
EXIF:FocalLength, EXIF:FocalLengthIn35mmFormat
FocalLength (0x920A) is the real optical focal length; FocalLengthIn35mmFormat (0xA405) is the full-frame equivalent. Crop factors, phone values, ExifTool.
ISO
EXIF:ISO, EXIF:SensitivityType, EXIF:RecommendedExposureIndex
EXIF:ISO (0x8827) stores sensor sensitivity as a 16-bit number, so it tops out at 65535. How SensitivityType and RecommendedExposureIndex fill the gap.
Metering mode
EXIF:MeteringMode
MeteringMode (0x9207) records how the camera measured light: average, center-weighted, spot or multi-segment. Value table and how vendor names map to it.
Scene capture type
EXIF:SceneCaptureType
SceneCaptureType (0xA406) records the scene mode: Standard, Landscape, Portrait or Night. What it leaves out, Samsung's extra value, and ExifTool commands.
Shutter speed
EXIF:ExposureTime, EXIF:ShutterSpeedValue
EXIF stores shutter speed twice: ExposureTime (0x829A) in seconds and ShutterSpeedValue (0x9201) in APEX. Why a 1/125 shot can read 1/128 in ExifTool.
White balance
EXIF:WhiteBalance, EXIF:LightSource, MakerNotes:ColorTemperature
EXIF WhiteBalance (0xA403) is only Auto or Manual. LightSource (0x9208) and maker-note color temperature hold the details. Real Canon output explained.
Date & time
Three EXIF dates, sub-seconds and time zone offsets. None of them is the file date your OS shows.
CreateDate
EXIF:CreateDate
CreateDate is ExifTool's name for EXIF DateTimeDigitized (0x9004): when it differs from DateTimeOriginal, as on scanned film, and how to set it.
DateTimeOriginal
EXIF:DateTimeOriginal, EXIF:SubSecTimeOriginal
DateTimeOriginal is the EXIF date taken: its YYYY:MM:DD HH:MM:SS format, the missing time zone, SubSecTimeOriginal, and how to fix it with ExifTool.
ModifyDate
EXIF:ModifyDate
ModifyDate is EXIF DateTime (0x0132) in IFD0: what updates it, why copying a file doesn't, how it differs from the file system date, and ExifTool fixes.
OffsetTime
EXIF:OffsetTime, EXIF:OffsetTimeOriginal, EXIF:OffsetTimeDigitized
OffsetTime, OffsetTimeOriginal and OffsetTimeDigitized store the UTC offset of EXIF dates. Format, EXIF 2.31 support, and inferring the zone from GPS.
GPS
Coordinates, altitude, direction and accuracy. The fields to check before you post a photo publicly.
GPS altitude
EXIF:GPSAltitude, EXIF:GPSAltitudeRef
GPSAltitude stores altitude in meters with the sign in GPSAltitudeRef. Why phone values are often ellipsoid heights, not sea level, and how to fix them.
GPS coordinates
EXIF:GPSLatitude, EXIF:GPSLatitudeRef, EXIF:GPSLongitude
How photo GPS coordinates are stored: GPSLatitude, GPSLongitude and their Ref tags, three DMS rationals, decimal conversion, and the XMP string copy.
GPS horizontal positioning error
EXIF:GPSHPositioningError
GPSHPositioningError (0x001F, EXIF 2.3) gives the horizontal error of a photo's GPS position in meters. How it differs from GPSDOP and what to do with it.
GPS image direction
EXIF:GPSImgDirection, EXIF:GPSImgDirectionRef
GPSImgDirection (0x0011) is the compass bearing of the camera, GPSImgDirectionRef (0x0010) says true or magnetic north. Format, pitfalls and privacy.
GPS timestamp
EXIF:GPSTimeStamp, EXIF:GPSDateStamp
GPSTimeStamp (0x0007) and GPSDateStamp (0x001D) store the UTC time of a photo's GPS fix. Encoding, ExifTool's GPSDateTime, lag, and how to edit or remove it.
Rights & description
Creator, copyright, credit and licensing fields from EXIF, IPTC and XMP, plus captions and keywords.
Artist
EXIF:Artist
EXIF Artist (0x013B) stores the image creator's name in IFD0. How cameras fill it, how it maps to dc:creator and By-line, and how to edit or clear it.
Copyright
EXIF:Copyright, IPTC:CopyrightNotice, XMP:Rights
Where a photo's copyright notice is stored: EXIF Copyright (0x8298), IPTC CopyrightNotice (2:116) and XMP dc:rights, plus the two-part EXIF convention.
Creator
XMP:Creator, IPTC:By-line, EXIF:Artist
Creator is stored as XMP dc:creator, an ordered list, with IPTC By-line (2:80) and EXIF Artist as copies. List handling, the 32-byte limit, and editing.
Credit line
IPTC:Credit, XMP:Credit
The credit line (IPTC Credit 2:110, XMP photoshop:Credit) is how a photo should be credited when published. Google reads it. Limits and how to set it.
Digital Source Type
XMP:DigitalSourceType
The IPTC Digital Source Type field says whether an image is a capture, a scan, a human creation or generative AI. Current values, C2PA link, how to set it.
Image description
EXIF:ImageDescription, IPTC:Caption-Abstract, XMP:Description
A photo caption lives in EXIF ImageDescription (0x010E), IPTC Caption-Abstract (2:120) and XMP dc:description. Camera filler, alt text, syncing all three.
Keywords
IPTC:Keywords, XMP:Subject, EXIF:XPKeywords
Photo keywords live in IPTC Keywords (2:25), XMP dc:subject and Windows XPKeywords. Storage, the 64-byte limit, and ExifTool commands without duplicates.
Licensor URL
XMP:LicensorURL, XMP:Licensor
Licensor URL is the IPTC/PLUS field behind the Get this image on link in Google Images. Where it is stored, how ExifTool shows it, and a multi-licensor trap.
Owner name
EXIF:OwnerName
OwnerName is ExifTool's name for EXIF CameraOwnerName (0xA430), the camera owner's name. Other tags with the same name, privacy risks, and how to clear it.
UserComment
EXIF:UserComment
UserComment (0x9286) is a free-text EXIF note whose first 8 bytes declare ASCII, UNICODE, JIS or undefined. Real hex dumps, pitfalls, and how to edit it.
Web Statement of Rights
XMP:WebStatement
What the XMP Web Statement of Rights field holds, why Google Images needs it for the Licensable badge, and how to write it with ExifTool.
Image & file structure
How the file is built: dimensions, orientation, color, compression and the version markers each standard leaves behind.
Bits Per Sample
EXIF:BitsPerSample, File:BitsPerSample, PNG:BitDepth
How bit depth is recorded in TIFF (BitsPerSample, 0x0102), PNG (IHDR bit depth) and JPEG (SOF precision), how ExifTool reports each, and when 16-bit helps.
Byte Order
File:ExifByteOrder
Every TIFF and EXIF block starts with II or MM, setting the byte order of every number after it. How to read ExifByteOrder, what cameras use, when it matters.
Chroma Subsampling
File:YCbCrSubSampling, EXIF:YCbCrSubSampling, EXIF:YCbCrPositioning
How to read YCbCrSubSampling in ExifTool, what 4:2:0, 4:2:2 and 4:4:4 mean, the real file size cost of 4:4:4, and what YCbCrPositioning is for.
Color Space
EXIF:ColorSpace, EXIF:InteropIndex
The EXIF ColorSpace tag only knows sRGB and Uncalibrated. How Adobe RGB is really signaled, what iPhones write, and why the ICC profile matters more.
Compression
EXIF:Compression
What the Compression tag means in TIFF and JPEG files, the common values (1, 5, 6, 7, 8, 32773) with ExifTool's names, and why relabeling it breaks a TIFF.
Current IPTC Digest
Photoshop:IPTCDigest, File:CurrentIPTCDigest
Photoshop stores an MD5 of the IPTC block so readers can spot stale XMP. How ExifTool compares IPTCDigest with CurrentIPTCDigest, and how to fix a mismatch.
Exif Version
EXIF:ExifVersion, EXIF:FlashpixVersion
ExifVersion stores four ASCII digits, not a number. What 0220 through 0300 mean, which version added OffsetTime, and why it is a claim, not a guarantee.
ICC Profile
ICC_Profile:ICC_Profile, ICC_Profile:ProfileDescription, ICC_Profile:ColorSpaceData
An embedded ICC profile tells apps what an image's RGB values mean. Where JPEG, PNG, WebP and TIFF store it, how to extract or keep it, what stripping does.
Image Width and Height
File:ImageWidth, File:ImageHeight, EXIF:ImageWidth
ImageWidth (0x0100), ExifImageWidth (0xA002) and the JPEG SOF size can all differ. Which one is the real pixel size, and what goes wrong after a resize.
Interoperability Index
EXIF:InteropIndex, EXIF:InteropVersion
InteropIndex in the Interoperability IFD says which DCF rule set a file follows: R98 for sRGB, R03 for Adobe RGB, THM for thumbnails. How to read and set it.
JFIF Version
JFIF:JFIFVersion, JFIF:ResolutionUnit, JFIF:XResolution
What the JFIF APP0 segment holds (version, density unit, X and Y density), why 1.01 is everywhere, how it clashes with EXIF DPI, and what stripping changes.
Orientation
EXIF:Orientation
EXIF Orientation tells viewers how to rotate or mirror the stored pixels. The 8 values in ExifTool's wording, who honors them, and why stripping turns photos.
Resolution (DPI)
EXIF:XResolution, EXIF:YResolution, EXIF:ResolutionUnit
What the EXIF XResolution, YResolution and ResolutionUnit tags control, why 72 dpi means nothing on screen, and how JFIF density can contradict EXIF.
Thumbnail Image
EXIF:ThumbnailImage, EXIF:ThumbnailOffset, EXIF:ThumbnailLength
Most camera JPEGs hide a small preview JPEG in IFD1. How ExifTool shows it, why it can still show the uncropped original, and how to extract or delete it.
XMP Toolkit
XMP:XMPToolkit
XMPToolkit names the library that serialized a file's XMP packet. Common values like XMP Core 6.0.0 and Image::ExifTool 12.76, and when the value changes.