This utility calculates the duration of audio files (both uncompressed, PCM/IEEE FP audio, such as “.WAV”, “.W64” “.AIFF/.AIF” and also compressed files such as MP3, WMA, AAC and OGG Vorbis) that will fit into your available disk space:
**N.B.** If you’re looking for a calculator to do the opposite (i.e. calculate the size of audio files from a given duration), then go here.
Enter your available disk/storage space. Calculating the duration of uncompressed files also requires the Sample Rate, Bit Depth and Channel information (but not the Bit Rate, which is automatically calculated). In addition to the available disk/storage space, calculating the duration of compressed files such as MP3 etc., requires only the Bit Rate information (in this case the Sample Rate, Bit Depth and Channel information is ignored). For compressed files encoded with CBR (Constant Bit Rate), the displayed duration should be as accurate as possible (notwithstanding variables such as header information etc- see below). For compressed files encoded with VBR (Variable Bit Rate), the displayed file size can be slightly less accurate because in this case the bit rate can vary depending on the programme material.
Note that the amount of available disk space reported by your device may vary slightly due to file allocation methods, possible differences in the amount of header information and/or the fact that some operating systems calculate hard disk space differently from others (e.g., some calculate it in binary and call 1kB 1024 bytes whilst others – and most hard drive manufacturers – calculate it in decimal and call 1kB 1000 bytes) – this calculator requires decimal input but also displays the equivalent binary value for convenience.
If you find this useful and/or have any comments or suggestions then do let me know via the comment section below.
Could you please share the formula to calculate duration for mp3 files, knowing size and bitrate?
Sure. The basic formula is: Duration (seconds) = File Size (bits) / Bit Rate (bits per second)
See also my comments above.
could you please tell me how to calculate AAC audio chunks duration of having sampling rate 44100.
Hi Mayank,
You’ll need to enter the bit rate for an AAC file as it’s a lossy format (similar to Mp3). A file that is originally recorded uncompressed at a sample rate of 44100 Hz won’t remain that way after conversion to AAC. Just type the file size into the available space field and then enter the bit rate of your AAC file and the calculator will give you the duration! Bear in mind that, as with all lossy formats, the result will be approximate but probably close enough to be useful.
Could you please add a 32khz sample rate option? Used by various old skool samplers (and even the volca sample I think)
Hi Dan,
OK – I’ve added 32kHz as an available sample rate as per your request (both in this and in the Audio File Size Calculator)
Wondefult! Thanks very much for the super quick resopnse.
My pleasure, Dan.
By the way, you may like to know I’ve just published a new MIDI Note to Audio Frequency Calculator. Do check it out.
As I said in the comments on the other calculator, the binary conversion is off. It only multiplies (or divides, in this case) by 1.024, when it should be 1.024^x, where x is 1 for K, 2 for M, 3 for G, and so on. I think it’s calculating the duration using the binary because when I enter a value in the MB field that results in 120.375 MiB, it gives me 11:38.775 duration WAV (44.1 16bit stereo), which is the same value that I need to input in the other editor to get this binary size. However, this means that entering a value with the correct MB or GB sizes gives the wrong result (meaning longer duration than the real one) – in my case 126.222 MB (correct for 120.375 MiB) gives a too high MiB (123.26) value, and therefore a too long duration. You get a wrong result in the other converter too, which gives you a smaller file size than real. The error compounds with higher prefixes (5% in Gigs).
Good catch Alex, thanks. Fixed.
Thanks for the very useful tool! Could you please also add 8kHz and 16kHz to the sampling rate drop-down list?
Done! Thanks for your comment – glad you find the calculator useful.
Cant get any result on my android phone (or am i blind? 😎)
Hmm, it works fine on android here. Make sure you have javascript enabled in your browser.
Thanks for this! But is there a minor bug? Going from disk space to duration, if I reset the form, enter units as GB, then enter 10 binary, it says 1 hour and something. If I add a decimal point and zero to make it 10.0, it reads what seems a lot more likely to be the right answer.
Hi Tony, Thanks for your comment. You are correct – there was indeed a bug concerning the binary input field. I’ve fixed it by disabling binary input altogether (although the correct binary value is still displayed when you enter the amount of disk space in decimal). All calculations should now be accurate. I’ll try to find a solution which allows binary input again when I have more time.
Actually, I’ve decided now not to allow binary input because a) no-one has complained about its’ absence and b) I don’t think it’s that useful these days anyway.
Thank you! Very helpful
**Updated** Now calculates compressed (MP3 etc.) as well as uncompressed files!
Thanks to everyone who contacted me requesting this – it took a while but I finally managed to find some time and…here it is! 🙂 Hope it’s useful to you. Let me know what you think in the comments…