What Does Date Modified Mean? Date Modified vs Date Taken
What does date modified mean? It is the last time a file was saved on this disk, not when the photo was taken. What changes it, and how to fix it.
Date modified is the last time the contents of a file were saved. The file system of your computer records it, not the camera. For a photo, it tells you when the file was last written on a disk, not when the picture was taken. That is why a ten-year-old photo can show a date modified of last Tuesday.
The date the picture was taken is a different field, Date taken, stored inside the photo. The two often disagree, and the rest of this page explains why and which one to trust.
Date modified meaning, in one table
Every file on Windows, Mac and Linux has file dates. A photo also has a date inside it.
| Date | Where it is stored | What it records |
|---|---|---|
| Date modified | File system | The last time the file's contents were saved |
| Date created | File system | The time the file appeared on this disk |
| Date accessed | File system | The last time the file was opened (often switched off) |
| Date taken | Inside the photo (EXIF DateTimeOriginal) | The moment the camera took the picture |
File dates belong to the copy on this disk. Date taken belongs to the picture and travels with it. Date taken meaning explains the date inside the photo in detail.
What changes date modified
These actions set date modified to the current time:
- Editing and saving a photo in any editor, including a rotate that saves the file.
- Writing metadata into the file, for example adding a date taken, a GPS location or a rating.
- Downloading the file in a browser, or saving an attachment from email or a chat app.
- Most transfers from a phone over a USB cable in "File transfer" (MTP) mode.
These actions usually keep it:
- Opening or viewing the file.
- Renaming the file.
- Copying or moving the file in File Explorer or Finder.
- Extracting a zip. The zip stores a modified time for each file, and the extractor puts it back.
Google Takeout is the extreme case. The files in the zips carry recent dates, not capture dates, so after you unzip, every photo shows the day of the export or the day you unzipped it, even photos from 2009. The real dates are in the .json files beside the photos. Google Takeout photos show the wrong date covers that case.
Date modified vs date created
Date created is the time the file appeared on this particular disk. A copy is a new file, so Windows gives it a new date created, while date modified comes over from the original. The result looks strange: a photo whose date created is later than its date modified. That is normal after a copy. On a Mac, Finder copies usually keep both dates.
Neither date says when the photo was taken.
Date modified vs date taken
Date taken is written by the camera into the EXIF block at the moment of capture. It stays the same when you copy, rename, upload or download the file. Photo apps sort by it: Apple Photos, Google Photos, Windows Photos, Immich and phone galleries all use date taken first and fall back to a file date only when date taken is missing.
File managers are different. File Explorer and Finder sort by file dates unless you choose otherwise. That is why the same folder looks correct in a photo app and shuffled in a file manager.
Screenshots, images saved from WhatsApp and most scans have no date taken at all. For those files, date modified is often the only date a program can find, so they land on the day they were copied.
How to see the dates
Windows 11: in File Explorer, switch to Details view, right-click any column heading and add "Date taken" and "Date created". For one photo, right-click it, choose Properties, then Details.
Mac: in Finder, choose View, Show View Options, and tick "Date Modified" and "Date Created". For the date taken, open the photo in Preview, press Command-I and open the EXIF tab.
Any system: exiftool prints every date at once with exiftool -time:all photo.jpg.
How to change date modified
For one file:
- Windows (PowerShell):
(Get-Item "photo.jpg").LastWriteTime = "2019-07-14 15:30" - Mac or Linux (Terminal):
touch -t 201907141530 photo.jpg
For a folder of photos that still have their date taken, copy date taken into the file dates with exiftool:
exiftool "-FileModifyDate<DateTimeOriginal" -r .Change date taken as well if it is missing or wrong, because that is the date photo apps use. How to change date taken on photos in Windows 11 shows the steps.
The app
Takeout JSON Metadata Fixer sets both at once: it writes the real date taken into each photo and sets date created and date modified to the same moment, so every program agrees.
For Google Takeout exports it reads the date from each .json file. For any other folder it uses the date already inside the photo. It runs offline on Windows and Mac. The first 500 photos are free.
Frequently asked questions
What does date modified mean on a photo?
The last time that copy of the file was saved. It is not the date the photo was taken.
Does opening a photo change date modified?
No. Only saving changes it. Some viewers save a rotation automatically, and that does change it.
Why is date modified older than date created?
The file was copied. The copy got a new date created, and kept the original date modified.
Which date should I sort my photos by?
Date taken. In File Explorer, add the "Date taken" column and sort by it. In a photo app, it is the default.