File Size and Record Time Calculations

TourMaster: Mono or Stereo PCM 16 Bit, 44.1 KHz WAV (Mono 5.292 MB per minute) (Stereo 10.584 MB per minute)

                    Mono 8GB Card = 1511 minutes (~25 hrs)

                    Mono 32GB card = 6046 minutes (~100 hrs)

                    Stereo 8GB card = 755 minutes (~12.5 hrs)

                    Stereo 32GB card = 3023 minutes (~50 hrs)

TriggerPoint: Mono PCM 16 Bit, 44.1 KHz WAV (Mono 5.292 MB per minute)

                     Mono 8GB Card = 1511 minutes (~25 hrs)

                     Mono 32GB card = 6046 minutes (~100 hrs)

TourMaster Lite: Mono 192 kbps MP3 (1.44 MB per minute)

                     Mono 8GB card = 5555 minutes (~92.5 hrs)

Handheld Audio Guide: Mono 128 kbps MP3 (960 KB per minute)

                     Mono 8GB card = 5555 minutes (~92.5 hrs)

Audio Guide 2: Mono 128 kbps MP3 (960 KB per minute)

                     Mono 8GB card = 5555 minutes (~92 hrs) * Can upgrade up to 16GB card


With file-based digital audio recorders, the calculation of available recording time involves three variables, track count, data rate, and storage medium capacity.

  • Track count – how many concurrent audio tracks/channels are to be recorded.
  • Data rate – expressed by sampling rate and bit depth for non-compressed audio and by bit rate for compressed (MP2 and MP3) audio data. Data rate determines how big the data “container” is for the audio signal. (See the calculation for determining PCM audio below.)
  • Storage medium capacity – typically expressed in GB (see Drive Notes below).

Audio File Size Calculations


These calculations will help you to estimate the size of audio files.

NOTES:
1) "x" means "multiplied by". Forward slash (/) means "divided by".
2) Kbps means "Kilobits per second" (1,000 bits per second). KB means KiloBytes (1,000 Bytes). There are 8 bits in a byte. Note the uppercase "B" for bytes in "KB". A lowercase "b" (Kb) would indicate bits.
3) Calculations for MP3 files generally include both left and right stereo channels. Calculations for PCM files must be multiplied by 2 to allow for both left and right stereo channels.
4) We took reasonable care in computing these figures, but you may want to doublecheck them if you're working on an important project. We did a casual experiment with a one-minute PCM file, and Windows Explorer reported it to be slightly smaller (10,337 KB) than what was predicted by the calculations below (10,584 KB). This may be due to differences between binary and decimal counting systems (multiples of 2 versus multiples of 10). In addition, file header information and ID3 tags (for MP3s) will have an effect on the numbers. In general, however, we have have found the figures below to be useful for approximating audio file sizes.


MP3 File Size Calculations

Formula:
Kbps = bits per second / 8 = Bytes per second x 60 seconds = Bytes per minute x 60 minutes = Bytes per hour

Bitrate File size
per second
File size
per minute
File size
per hour
8 Kbps 1 KB 60 KB 3.6 MB
16 Kbps 2 KB 120 KB 7.2 MB
32 Kbps 4 KB 240 KB 14.4 MB
40 Kbps 5 KB 300 KB 18.0 MB
48 Kbps 6 KB 360 KB 21.6 MB
56 Kbps 7 KB 420 KB 25.2 MB
64 Kbps 8 KB 480 KB 28.8 MB
80 Kbps 10 KB 600 KB 36.0 MB
96 Kbps 12 KB 720 KB 43.2 MB
112 Kbps 14 KB 840 KB 50.4 MB
128 Kbps 16 KB 960 KB 57.6 MB
160 Kbps 20 KB 1.20 MB 72.0 MB
192 Kbps 24 KB 1.44 MB 86.4 MB
224 Kbps 28 KB 1.68 MB 100.8 MB
256 Kbps 32 KB 1.92 MB 115.2 MB
320 Kbps 40 KB 2.40 MB 144.0 MB

PCM File Size Calculations

Here are some file size calculations for common PCM audio settings. PCM stands for Pulse Code Modulation and commonly uses the file extensions .wav or .cda. There are quite a few other combinations of bits per sample and samples per second which may be used. We have included calculations for the most common mono (one channel) and stereo (two channel) settings.

Mono

Formula:
Bits per sample x samples per second = bits per second / 8 = Bytes per second x 60 seconds = Bytes per minute x 60 minutes = Bytes per hour of mono.

Settings Bitrate File size
per second
File size
per minute
File size
per hour
16 bit, 44.1 KHz 705.6 Kbps 88.2 KB 5.292 MB 317.52 MB
16 bit, 48 KHz 768 Kbps 96 KB 5.750 MB 345.60 MB
24 bit, 48KHz 1,152 Kbps 144 KB 8.640 MB 518.40 MB
24 bit, 96KHz 2,304 Kbps 288 KB 17.280 MB 1.0368 GB

Stereo

Formula:
Bits per sample x samples per second = bits per second x 2 channels = bits per second of stereo / 8 = Bytes per second of stereo x 60 seconds = Bytes per minute of stereo x 60 minutes = Bytes per hour of stereo.

Settings Bitrate File size
per second
File size
per minute
File size
per hour
16 bit, 44.1 KHz 1,411.2 Kbps 176.4 KB 10.584 MB 635.04 MB
16 bit, 48 KHz 1,536 Kbps 192 KB 11.520 MB 691.2 MB
24 bit, 48KHz 2,304 Kbps 288 KB 17.28 MB 1.036 GB
24 bit, 96KHz 4,608 Kbps 576 KB 34.56 MB 2.0736 GB

Calculations