I just had a look and this is the data I see from your file after downloading:ĭuration: 1 hour, 14 minutes, 3 seconds, 984 millisecondsįile size (decimal): 71.1 MB (71,103,822 bytes) You can then convert to mp3 (or whatever other format may be required) for delivery, keeping the original WAV files intact in case you might need to convert them to a different format later without any loss of audio quality. Personally, I would always record spoken material (music is a little different) as a standard WAV file at either 44.1kHz/16-bit or 48kHz/16-bit. Mp3 is fine as a delivery format but (for several reasons too involved to go into here) far from ideal as a recording format. Since you ask for my advice I suggest that you always record to WAV files in future (which are uncompressed and non-lossy) and NOT mp3 (which are both compressed AND lossy). However, the way I would deal with this (short of re-recording) would be to convert the files to WAV (at 44.1kHz/16-bit), and then to FLAC (which is compressed but non-lossy) and use that as the delivery format – that way you won’t lose any quality from your original files. Because mp3 is a lossy format, re-encoding to mp3 at 192 kbps will inevitably degrade quality (which may or may not be acceptable to you). In any case, it sounds like you recorded your files at either 128 or 129 kbps instead of the required 192 kbps, so you’ll need to correct them before submission. I took a look at their technical requirements and your distributor seems to require either mp3 files at 192 kbps or FLAC files at a sample rate of 44.1 kHz (and, presumably, because they don’t make this clear, 16-bit). It also sounds as though you perhaps used a variable bit rate (VBR) because 129 kbps (the files can’t possibly be 129 bps – that would be a ridiculously low bit rate) is not quite standard for CBR (continuous bit rate) mp3 files – although 128 kbps IS a standard bit rate, so this could simply be a reporting error. The basic formula is: File Size (bits) = Duration (seconds) * Bit Rate (bits per second). It’s important to realise that mp3 file codecs (CODEC is short for encode/decode) are usually expressed in kbps, which stands for kilobits PER SECOND, in other words, this is the amount of data which is streamed per-second when you play the file, which is why it’s called the bit rate – it DOES NOT refer to the total number of bits in the file itself the file size is determined by the duration of the encoded audio multiplied by the bit rate. It sounds as though you have recorded your audio book as mp3 files, yes? In terms of mp3 file encoding, describing a file as 128 or 129 “bits” makes no sense. If you find this useful and/or have any comments or suggestions then do let me know via the comment section below (please read our website rules before posting). Note that the file size reported by your device may vary slightly from that shown 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 handles both methods.

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.

For compressed files encoded with CBR (Constant Bit Rate), the displayed file size should be as accurate as possible (notwithstanding variables such as header information etc- see below). requires only the Bit Rate information (in this case the Sample Rate, Bit Depth and Channel information is ignored). In addition to the duration, calculating the size of compressed files such as MP3 etc. Calculating the size of uncompressed files also requires the Sample Rate, Bit Depth and Channel information (but not the Bit Rate, which is automatically calculated). Duration Hours: Minutes: Seconds: Milliseconds: Settings - Uncompressed (WAV, AIFF etc.) Sample Rate: Bit Depth: Channels: Settings - Compressed (MP3, AAC etc.) Bit Rate (kbps): (kilobits per-second) Reset Uncompressed (WAV, AIFF etc.) Bit Rate: 1411.2 kbpsĠ Compressed (MP3, AAC etc.) Bit Rate: 0 kbpsĮnter the duration of your file in hours, minutes, seconds and milliseconds.

16 bit resolution calculator