Maximum length for imported file

I have a long audio track. (2.5 hours)
O can’t seem to import it into audacity (for mac)
Is there a maximum track length.
I’ve tried searching the help manual using the terms “maximum” and length.

What kind of file is it? If it’s something Audacity doesn’t recognize, it could be any length and Audacity won’t open it.

Make sure your’e in Audacity 2.1.1 and install the FFMpeg software package. It’s an extender for different types of sound files. Scroll down.

Do you know anything else about it? Does it open in QuickTime Player? Control-Click the file > Open With: QuickTime Player.


It was ACC.
I’ll convert it to mp3 and go from there.
I assume that’s the problemThanks.

ACC or AAC? AAC is a recognized Apple/iTunes format.
You should avoid converting the work to another compressed format like MP3. Each time you do that you pick up additional compression sound damage from each format. Convert to WAV if you can. The quality of the sound won’t get any better, but it won’t get any worse.


You solved my current issue but I’d still like to know if there a length or size maximum for audacity.
I can imagine scenarios where I make a very long recording.
i.e. Recording a radio station all night long.

If you’re recording something plugged into the side of the computer, the limit used to be 13 hours at Audio CD rates: 44100, 16-bit, Stereo. I think that limit went away several versions back. Too many people needing surveillance recorders ran into it.

Make sure your computer doesn’t try to update itself, go to sleep, etc, etc, etc. Make sure all the Auto Update systems are set to operator will tell you what to do.

There is still a very definite limit on exported files. WAV is 2GB or 4GB depending on where you’re going with it. I think Broadcast WAV has similar problems. You should look up the limit on MP3 files. The problem with MP3 is the compression sound damage. There is always some and you can’t stop it.

But I don’t think there is a record all night problem with Audacity.


The 13 hour limit has mostly been solved (this is actually based on the total length in samples and the limit was 2^31 samples, which is 2147483648 samples. At 44100 samples per second, that works out as 48696 seconds = 13 hours 31 minutes and 35 seconds).
There are still some glitches that occur beyond this length that are still to be resolved, but as far as I’m aware they are non-fatal.

In nearly all cases these days it is the 4GB limit that applies. This is the limit of how many samples a standard WAV file with a 32-bit header can handle. I think this works out as a bit over 6 1/2 hours for CD quality stereo.

2.5 hours should be fine as long as you have plenty of free disk space, though working with long files can be quite slow due to the large amounts of data that get shunted around.

The first thing that I would do with a very long recording is to split it up into more manageable size chunks, say around 1 hour each, and save each of those chunks as a separate file. Working on a 1 hour chunk is likely to be much quicker and easier than working on a multi-hour project and avoids the file format problems.

Note that in WAV format, or any other uncompressed format, mono files are half the size of stereo file of the same length. For compressed formats such as MP3 or AAC, mono files can have noticeably better sound quality than a stereo file of the same size. The upshot being that it can be advantageous to make very long recordings in mono rather than stereo.