# Not possible to save track numbers with leading zero in m4a
**URL:** https://community.mp3tag.de/t/not-possible-to-save-track-numbers-with-leading-zero-in-m4a/49664
**Category:** Support
**Created:** [July 19, 2020, 6:03pm UTC](https://community.mp3tag.de/t/not-possible-to-save-track-numbers-with-leading-zero-in-m4a/49664 "2020-07-19T18:03:56Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@adkurz](https://community.mp3tag.de/u/adkurz)
#### Post date: [July 19, 2020, 6:03pm UTC](https://community.mp3tag.de/t/not-possible-to-save-track-numbers-with-leading-zero-in-m4a/49664/1 "2020-07-19T18:03:56Z")
Hello,
In mp3tag, it's not possible to save track numbers with leading zeros in m4a files.
If I write 01 or 001 as track number, mp3 tag only saves 1. In other formats like MP3 or FLAC, the problem doesn't exists. In other programs, like Foobar2000, the leading zeros work, but mp3tag shows only 1 instead of 01 or 001.
Is there the possibility to fix this?
System: Win10 x64, latest mp3-tag-Version, German system.
Greetings Adrian Kurz
---
### Author:  [@ohrenkino](https://community.mp3tag.de/u/ohrenkino)
#### Post date: [July 19, 2020, 6:05pm UTC](https://community.mp3tag.de/t/not-possible-to-save-track-numbers-with-leading-zero-in-m4a/49664/2 "2020-07-19T18:05:44Z")
> [@adkurz](#):
>
> Is there the possibility to fix this?
Not really.
The mp4 tags do not allow leading zeros as the track number is really a number and not a "numeric string" as for mp3 files.
If you want to adapt the display in MP3tag, you could try
`$num(%track%,2)`for the setting in "Value" for the column definition.
(This will not show the number total tracks, though).
See also here:
> [@\[X\] Auto-numbering with leading zero fails](https://community.mp3tag.de/t/x-auto-numbering-with-leading-zero-fails/13064/):
>
> Hi Developers, I just installed v2.49b. There's a problem with auto-number tagging. Here's how to reproduce Choose more than 10 files Select the Auto-number wizard (Ctrl+K) Check the "leading zeros for tracknumbers..." checkbox Apply and save the files Refresh and see that leading zeros are not applied for track numbers 1-9 Thanks
---
### Author:  [@system](https://community.mp3tag.de/u/system)
#### Post date: [February 9, 2026, 12:28pm UTC](https://community.mp3tag.de/t/not-possible-to-save-track-numbers-with-leading-zero-in-m4a/49664/3 "2026-02-09T12:28:43Z")