Audio Recording Time Calculator – File Size & Bitrate Estimator

For uncompressed audio (WAV, AIFF), the formula is:
File Size (bytes) = Sample Rate (Hz) × Bit Depth ÷ 8 × Number of Channels × Duration (seconds)

For example, CD-quality audio (44,100 Hz, 16-bit, stereo) produces about 10.1 MB per minute. For compressed formats like MP3, use: File Size = Bitrate (bps) × Duration (seconds) ÷ 8. Our calculator handles all these conversions automatically.

Sample Rate (Hz) is how many times per second the audio is measured — higher means better high-frequency response. Bit Depth determines the dynamic range (16-bit = 96dB, 24-bit = 144dB). Bitrate (kbps) applies to compressed audio and represents the amount of data used per second. For uncompressed audio, the effective bitrate is Sample Rate × Bit Depth × Channels.

It depends on your settings. At CD quality (44.1kHz/16-bit/Stereo WAV), a 32GB card holds approximately 33 hours of audio. At studio quality (48kHz/24-bit/Stereo WAV), about 20 hours. With MP3 at 320kbps, you can record roughly 222 hours. Use the "File Size → Time" mode above to calculate for your specific setup.

WAV offers completely lossless, uncompressed audio — best for recording and editing but creates large files. FLAC provides lossless compression (about 40-60% smaller than WAV) with identical audio quality, making it ideal for archiving. MP3 and AAC use lossy compression to dramatically reduce file size (80-90% smaller) at the cost of some audio fidelity — great for streaming and casual listening. For professional work, stick with WAV or FLAC.

Podcasts / Voice: 44.1kHz, 16-bit, Mono — more than sufficient for speech.
Music production: 48kHz or 96kHz, 24-bit — provides headroom for mixing and processing.
Video / Film: 48kHz, 24-bit — matches video standards.
Mastering / Archival: 96kHz, 24-bit or 32-bit float — maximum quality preservation. Higher settings mean larger files, so balance quality with storage constraints.

Yes, for uncompressed formats like WAV and AIFF, stereo requires exactly twice the data of mono because two independent audio channels are stored. For compressed formats like MP3, the relationship is more complex — joint stereo encoding can reduce the overhead, but stereo files are still noticeably larger than mono at the same quality settings.

Several factors can cause small discrepancies: file headers and metadata (ID3 tags, RIFF chunks), block alignment padding in WAV files, variable bitrate encoding in compressed formats, and filesystem cluster sizes. Our calculator provides a very close estimate — typically within 1-2% of the actual file size for uncompressed formats and within 5% for compressed formats.