Podcast Audio File Size Calculator
Estimate a podcast episode's audio file size from its length and encoding (MP3/AAC/OGG bitrate or WAV/FLAC), then project monthly and yearly hosting storage plus CDN bandwidth from your episode cadence and download count.
Input
Episode length
Encoding
Hosting estimate
Bandwidth = one full download per listener, per episode.
Output
Binary units (1 KB = 1024 bytes) — matches how Windows/macOS file managers show sizes.
| Metric | Value |
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Guides
Estimate how big a podcast episode will be, then see what publishing it costs in storage and bandwidth. Enter the episode length and how you plan to encode it — MP3/AAC/OGG at a chosen bitrate, or a WAV/FLAC master — and the calculator returns the per-episode file size plus a monthly and yearly hosting projection based on your release cadence and download numbers.
How to use it
- Set the episode length in hours, minutes and seconds.
- Pick an audio format. For MP3, AAC and OGG choose a bitrate (128 kbps is the standard podcast choice; 64–96 kbps is fine for spoken word). For WAV and FLAC set the sample rate, bit depth and channels instead — these are the parameters that determine an uncompressed file's size.
- Enter your episodes per month and average downloads per episode.
Results update as you type: file size per episode, monthly and yearly storage, and the bandwidth your host or CDN serves per episode and per month.
How the numbers are calculated
- Compressed (MP3 / AAC / OGG):
size = bitrate ÷ 8 × duration. The bitrate already encodes the channel and quality trade-off, so mono vs. stereo doesn't change a compressed file's size — only the bitrate does. - Uncompressed WAV:
size = sample rate × bit depth ÷ 8 × channels × duration. - FLAC: lossless compression is content-dependent, so it's estimated at about 65% of the equivalent WAV size — a realistic planning figure rather than an exact byte count.
- Hosting: monthly storage is the episode size times episodes per month (yearly is ×12). Bandwidth assumes one full download per listener: per-episode bandwidth is episode size × downloads, and monthly bandwidth multiplies that by your episode count.
Why does the size differ from my host's quota?
Sizes here use binary units (1 KB = 1024 bytes, 1 MB = 1024 KB), the same way Windows Explorer and macOS Finder report a file's size. Some hosts advertise storage in decimal units (1 MB = 1,000,000 bytes), which makes their quota look about 5% larger for the same file. Compare byte counts, not just the "MB" label, when you're close to a limit.
What bitrate should a podcast use?
For talk and interview shows, 96–128 kbps is the common sweet spot — indistinguishable from higher rates for voice while keeping downloads small. Music-heavy shows benefit from 192–256 kbps. Going above 320 kbps rarely helps a podcast and just inflates every listener's download.
Privacy
The calculation runs entirely in your browser — no audio, durations or listener numbers are uploaded anywhere.