Use this free audio file size calculator to work out exactly how much storage your recordings will need before you hit export. It handles both lossless formats like WAV and AIFF and compressed formats like MP3 and AAC, so whether you're archiving a multitrack session or exporting a podcast for distribution, you'll know the exact number in seconds.
Simply choose your format type, enter your sample rate, bit depth, channels (or bitrate for compressed files) and duration, and the calculator updates your file size in real time — no "Calculate" button required.
How to Use This Calculator (3 Steps)
- Step 1 — Pick your format type. Choose "Uncompressed" for WAV/AIFF or "Compressed" for MP3/AAC.
- Step 2 — Enter your audio settings. For uncompressed files, set sample rate, bit depth, and channels. For compressed files, set the bitrate.
- Step 3 — Enter your duration and read the result. The file size updates instantly in MB and GB, and you can tap "Copy Result" to paste it anywhere.
How to Calculate Audio File Size
Every audio file's size boils down to one of two calculations depending on whether the format is uncompressed (lossless PCM audio) or compressed (lossy or bitrate-based). Here's exactly how each one works, with a real-world example for each.
Uncompressed Audio Formula (WAV, AIFF)
Uncompressed formats like WAV and AIFF store every single sample of audio data with no data reduction, so file size is purely a function of four variables: sample rate, bit depth, channel count, and duration.
File Size (bytes) = Sample Rate (Hz) × Bit Depth (bits) × Channels × Duration (seconds) ÷ 8Worked example: a 5-minute (300-second) mono vocal take recorded at 48 kHz / 24-bit:
48,000 Hz × 24 bits × 1 channel × 300 seconds ÷ 8 = 43,200,000 bytes ≈ 43.2 MBSwitch that same take to stereo and the file size simply doubles to roughly 86.4 MB — which is exactly what the calculator above will show you if you change the Channels field.
Compressed Audio Formula (MP3, AAC)
Lossy formats like MP3 and AAC don't store raw samples — they use psychoacoustic encoding to discard data the human ear is unlikely to notice. Because of this, sample rate, bit depth, and channel count barely move the needle. Instead, file size is driven almost entirely by bitrate (the amount of data used per second of audio) and duration.
File Size (bytes) = Bitrate (kbps) × 1,000 × Duration (seconds) ÷ 8Worked example: a 1-hour (3,600-second) podcast episode encoded at 128 kbps:
128 kbps × 1,000 × 3,600 seconds ÷ 8 = 57,600,000 bytes ≈ 57.6 MBThis is the exact same math the calculator runs when you switch to the "Compressed" tab — try entering 128 kbps and a 1-hour duration to confirm it matches.
Understanding Audio File Parameters
To get accurate results out of any audio file size calculator, it helps to understand what each input actually controls — both in terms of sound quality and storage cost.
What is Bit Depth?
Bit depth defines how many possible amplitude values can be recorded for each individual sample — essentially the "resolution" of your audio's loudness range. Common values are 16-bit (CD quality), 24-bit (the studio recording standard), and 32-bit float (used for high-headroom recording and mastering). Every extra bit roughly doubles the number of possible values and adds about 6 dB of usable dynamic range — but it also increases file size proportionally.
How Sample Rate Affects File Size
Sample rate determines how many "snapshots" of the audio waveform are captured every second, measured in Hz or kHz. The two most common rates are 44.1 kHz (the CD/music distribution standard) and 48 kHz (the video and broadcast standard), with 88.2 kHz, 96 kHz, and 192 kHz reserved for high-resolution recording and mastering work. Because sample rate is multiplied directly into the file size formula, doubling it doubles your file size for the same duration.
Mono vs. Stereo vs. Surround
Channel count multiplies directly into the file size formula, so more channels means proportionally more data. A mono recording uses one channel, stereo uses two (left and right), and surround formats like 5.1 and 7.1 use six and eight channels respectively.
| Channel Format | Channel Count | Relative File Size |
|---|---|---|
| Mono | 1 | 1× (baseline) |
| Stereo | 2 | 2× mono |
| 5.1 Surround | 6 | 6× mono |
| 7.1 Surround | 8 | 8× mono |
If you're deciding between mono and stereo for a vocal-heavy podcast or voiceover project, our guide on recording basics covers when each choice actually makes a practical difference to your mix.
Audio Format Size Comparison
Here's how one minute of stereo audio compares across the most common formats. This table assumes 44.1 kHz / 16-bit stereo as the uncompressed baseline, and a typical FLAC compression ratio of ~55%.
| Format | Typical Setting | Size Per Minute | Size Per Hour |
|---|---|---|---|
| WAV / AIFF | 44.1kHz, 16-bit, stereo | ≈ 10.6 MB | ≈ 635 MB |
| FLAC (lossless) | ~55% of WAV size | ≈ 5.8 MB | ≈ 350 MB |
| AAC | 256 kbps | ≈ 1.92 MB | ≈ 115 MB |
| MP3 | 320 kbps (max quality) | ≈ 2.4 MB | ≈ 144 MB |
| MP3 | 128 kbps (standard) | ≈ 0.96 MB | ≈ 57.6 MB |
Notice how uncompressed WAV audio is roughly 4-11× larger than any compressed format. That gap is exactly why professional studios record and edit in WAV for quality, then bounce down to MP3 or AAC only for final distribution. If you're still finalizing your recording chain, see our guide to the best DAW software for export options that support all of these formats natively.
Frequently Asked Questions
What is the best audio format for podcasting?
MP3 at 128–192 kbps is the most practical choice for podcasting — it's universally compatible, keeps download sizes small for listeners on mobile data, and 128 kbps is already considered "standard" quality for spoken-word content. If you're delivering to platforms that accept lossless masters, export a WAV for archiving and let the distributor handle the MP3 conversion.
How large is a 1-hour WAV file?
A 1-hour WAV file at the standard 44.1 kHz, 16-bit, stereo settings is approximately 635 MB. At 48 kHz / 24-bit stereo (a common studio recording setting), that same hour grows to roughly 1.03 GB. Use the calculator above to get an exact figure for your specific sample rate and bit depth.
Does FLAC reduce audio file size without losing quality?
Yes. FLAC (Free Lossless Audio Codec) is a lossless format, meaning it reduces file size by removing statistical redundancy rather than audio information — the decompressed audio is bit-for-bit identical to the original. Typical compression ratios land between 40–60% of the original WAV size, depending on the density of the source material.
What is the difference between 44.1kHz and 48kHz?
44.1 kHz is the historical CD and music distribution standard, while 48 kHz is the standard for video, broadcast, and most modern DAW sessions. Both comfortably exceed the ~20 kHz upper limit of human hearing according to the Nyquist theorem, so the audible difference is minimal — the choice mostly comes down to your delivery format. Since 48 kHz has a higher sample rate, it produces a slightly larger file at the same bit depth and duration.
Does bit depth or sample rate affect file size more?
Both scale file size linearly and by the same mathematical weight in the formula, but in practice sample rate changes tend to be larger jumps (e.g., 44.1 kHz to 192 kHz is a 4.4× increase) than typical bit depth changes (16-bit to 24-bit is only a 1.5× increase). Channel count and duration have the same linear effect as either variable.
Plan Your Storage and Bandwidth
Once you know roughly how large your files will be, the next step is making sure you actually have somewhere fast and reliable to put them. A single day of multitrack 24-bit/48kHz recording can easily produce several gigabytes of data, and that adds up fast across an album or a season of episodes.
If you're spec'ing out a new rig entirely, our guide to computer specs for music production covers exactly how much primary and secondary storage you should budget for based on your typical project size.
More Free Tools for Your Home Studio
- Studio Room Mode Calculator — find problem frequencies in your room before you treat it.
- BPM to MS Calculator — convert tempo to delay and reverb timing instantly.
- Tempo Change Pitch Shift Calculator — work out pitch shifts for tempo-changed audio.
- Free Online Metronome — a simple click track with tap-tempo detection.
Bookmark this audio file size calculator so it's ready the next time you need to plan storage, check an upload limit, or choose the right export settings for a project — and share it with your production team so everyone's estimating from the same numbers.