Audio Track Storage Calculator

The PCM storage formula

Uncompressed digital audio — PCM, the format sitting inside a WAV, AIFF or BWF file — has no hidden compression factor. Every sample, on every channel, is stored at its full bit depth, all the time. That makes the math exact rather than an estimate:

bytes per second = sample rate × (bit depth ÷ 8) × channel count

Work through the industry-standard broadcast master — 48 kHz, 24-bit, stereo:

48,000 samples/sec × (24 bits ÷ 8 bits/byte) × 2 channels

= 48,000 × 3 bytes × 2 = 288,000 bytes/second

Multiply by seconds to get a total. One hour is 3,600 seconds:

288,000 B/s × 3,600 s = 1,036,800,000 bytes ≈ 1.04 GB (decimal)

Scale that same 48 kHz/24-bit rate to a 64-track stem or Dante multitrack session — the exact scenario a location recordist or a dub stage runs on a feature mix — and one hour becomes:

48,000 × 3 × 64 = 9,216,000 B/s → × 3,600 s = 33,177,600,000 B ≈ 33.2 GB per hour

That's the entire formula. No codec, no quality slider, no "it depends" — sample rate, bit depth and channel count fix the byte rate completely, and duration scales it linearly from there.

Reference table: common configurations

Every cell is sample rate × (bit depth ÷ 8) × channels, scaled by 60 or 3,600 seconds — the calculator above runs the identical formula on whatever you enter.

The WAV 4 GB ceiling

Classic WAV files use the RIFF container format, and RIFF's chunk-size field is a 32-bit unsigned integer — it can only count up to 2³² − 1 bytes. In practice that caps a standard WAV at 4,294,967,296 bytes (2³²), not the 4,000,000,000-byte figure the "4 GB" shorthand suggests.

At 48 kHz/24-bit stereo (288,000 B/s), that ceiling arrives at:

4,294,967,296 B ÷ 288,000 B/s ≈ 14,913 seconds ≈ 4 hours 8 minutes

Past that point a strict RIFF WAV either truncates, corrupts its size header, or simply refuses to write further — and it happens quietly. Most professional recorders and DAWs (Sound Devices, Zoom, Pro Tools, Nuendo) detect the approach and silently switch to RF64 or BWF (Broadcast Wave Format) with a 64-bit size extension, or split into a new file — a poly-WAV — so the recording keeps going without an obvious warning on the transport. If you are hand-rolling WAV output, transferring raw files, or writing your own recorder, this is the number to design around; RF64/BWF removes the ceiling entirely by extending the size field to 64 bits.

32-bit float: headroom, not size

32-bit float uses 4 bytes per sample — exactly the same storage as 32-bit fixed-point integer, and 33% more than 24-bit (4 bytes vs 3). The benefit of float is headroom, not extra space: a float sample can represent values far above 0 dBFS without hard-clipping, so a level that would destroy a 24-bit fixed recording can often still be pulled back down in post. Field recorders increasingly default to 32-bit float for exactly this reason — it trades a predictable, moderate size increase for effectively eliminating clipped location audio.

Decimal vs binary units — why your OS shows a smaller number

This calculator reports storage the way drive manufacturers and most delivery specs do: decimal megabytes and gigabytes, where 1 MB = 1,000,000 bytes and 1 GB = 1,000,000,000 bytes. Operating systems, however, typically report binary MiB/GiB (1 MiB = 1,048,576 bytes; 1 GiB = 1,073,741,824 bytes) while still labeling them "MB"/"GB". The byte count never changes — only the unit does — but binary units divide by a bigger number, so the same file reads roughly 7% smaller in Finder or Explorer than the decimal figure you'd calculate by hand. A secondary MiB/GiB readout sits next to every decimal result above so the two never get confused.

PCM math vs bitrate math

Uncompressed PCM size is deterministic: multiply sample rate, bit depth, channels and duration, and you have the exact byte count — no lookup table, no encoder-dependent variance. Compressed formats (MP3, AAC, Opus) work the opposite way: size is driven by a target bitrate you choose, and the encoder throws away or re-quantizes audio information to hit it, so two files at the same bitrate from different encoders can differ slightly in size. If you're sizing a compressed delivery file rather than an uncompressed master, the Bitrate Converter is built for exactly that math.

1. Set the sample rate, bit depth and channel count for your session, from 44.1 kHz mono up to a 192 kHz 64-track multitrack.

2. Enter the duration you plan to record or deliver.

3. Read the exact size, watch the WAV 4 GB ceiling warning, and plan the card copy with the Offload & Checksum Time Calculator.