Rename files by modified date
Rename files by modified date using a UTC date prefix on copies of selected files. The original files are not changed. Free to use, with no sign-up required.
Files processed on your deviceFiles are read in this tab only. Nothing is uploaded.
01 How it works
- Choose one or more files.
- Use each file's modified timestamp to create a UTC date prefix.
- Download the renamed files as a ZIP.
02 Good to know
The date comes from the selected file's last-modified value as provided by the operating system or browser. It may be missing or inaccurate; the original files are not changed. Up to 1,000 files and 1 GiB total.
03Create date-prefixed filenames
Select files to create renamed copies with a date prefix based on each file's modified timestamp. Forkgen uses the timestamp supplied with the selected file and formats its date in UTC, then packages the renamed files in a ZIP download.
For example, a file named notes.txt with a modified date of 2026-04-09 receives a 2026-04-09 prefix. The ZIP contains renamed copies; the originals on your device stay as they are.
04Modified date is not the capture date
A modified timestamp records when the file was last changed according to the file system or browser metadata. It may not be the date a photo was taken or a document was first created, and copying or editing a file can change it.
Check the source dates before relying on the prefixes for records or sorting. A missing or inaccurate timestamp can produce a date that does not reflect the event you care about.
05Selection limits
The tool processes only files you select, up to 1,000 files and 1 GiB total. It does not rename files in place or scan folders automatically.
06 Questions
Which date does the filename use?
The selected file's modified timestamp, formatted as a UTC date.
Does it use a photo's EXIF capture date?
No. It uses the modified timestamp and does not read EXIF capture dates.
Are the original files renamed?
No. The tool creates date-prefixed copies in a ZIP download.
Can a modified date be inaccurate?
Yes. It depends on the timestamp supplied by the operating system or browser and may be missing or inaccurate.