Audio File Size Calculator — WAV, MP3, AAC, FLAC and Recording Time

For uncompressed PCM, WAV, AIFF, and Broadcast WAV, the core math is sample rate × bit depth × effective channels ÷ 8 = bytes per second. Effective channels are either your selected channel count (single-file mode) or channels per track × track count in multitrack mode. Total bytes are bytes per second × duration, plus optional WAV overhead when enabled.

For compressed MP3, AAC, and OGG-style estimates, the calculator uses file size = bitrate × duration ÷ 8. For FLAC, it starts with the WAV/PCM size and applies an estimated compression range, because FLAC size depends on the source material.

• Use one-click presets to jump between WAV/PCM, MP3, AAC, podcast, YouTube-style, and FLAC estimates quickly.
• Enter duration as fields or flexible text like 1:30:00, 90m, or 5400s.
• Switch to multitrack mode to estimate total session footprint across many tracks.
• Use storage size to estimate recording time on 32 GB, 64 GB, 128 GB, or 1 TB media.
• Use Scenario B compare and safe planning buffers (+10% / +20%) before media planning.
• Check card-fit estimates to see roughly how long 32 GB, 64 GB, 128 GB, and 1 TB media will last.

Audio file size depends on whether the audio is stored as uncompressed samples or as a compressed bitrate stream.

Use hertz for sample rate, bits for bit depth, channels as a count, seconds for duration, and bits per second for bitrate. Divide by 8 because there are 8 bits in one byte.

WAV and AIFF files are usually predictable because PCM stores every sample directly. These examples use binary units, so 1 MiB is 1,048,576 bytes.

Compressed formats are usually much smaller than WAV because they store fewer bits per second. FLAC is different: it is lossless, but its compression ratio changes with the source audio.

One minute of audio can be less than 1 MiB for a low-bitrate podcast file or more than 60 MiB for high-resolution stereo WAV. The most important inputs are bitrate for compressed audio and sample rate, bit depth, and channels for uncompressed audio.

The reverse recording-time calculator uses the same selected format settings as the file-size calculator. For WAV and PCM, recording time depends on sample rate, bit depth, and channel or track count. For MP3, AAC, OGG, and other bitrate-based formats, recording time depends mainly on the chosen kbps value.

Use the storage size input for a specific card, recorder drive, or delivery limit, then compare it with the quick 32 GB, 64 GB, 128 GB, and 1 TB estimates in the result panel.

WAV files are often larger because they normally contain uncompressed PCM audio. A 48 kHz, 24-bit stereo WAV stores 2,304,000 bits every second, regardless of whether the audio is loud, quiet, simple, or complex. MP3 and AAC use codec compression and a target bitrate such as 128 kbps or 320 kbps, so they store far fewer bits per second.

That smaller MP3 or AAC size is useful for delivery, streaming, and archives where space matters. WAV, AIFF, and Broadcast WAV remain common for recording, editing, mixing, mastering, and production handoff because they preserve the original PCM samples without lossy codec decisions.

Storage manufacturers usually label drives in decimal units: 1 GB is 1,000,000,000 bytes. Many operating systems and recording tools report binary units: 1 GiB is 1,073,741,824 bytes. That is why a 64 GB card may appear as about 59.6 GiB.

The calculator includes a unit selector so you can switch between decimal MB/GB and binary MiB/GiB. Decimal units are useful for matching storage labels, while binary units are useful when comparing against operating-system file sizes.