Audacity's manual gives a direct answer for podcasts: use CBR, not VBR. Its MP3 Export Options page says it in one line — "For podcasts, "CBR" (Constant Bit Rate) is recommended, and not "VBR" (Variable Bit Rate)." — and then lists five specific settings you can copy straight across.
That is worth knowing because Audacity's own defaults point the other way. This page walks through the recommended settings and the export dialog steps around them. You need a finished edit open in Audacity; on Windows and Mac nothing else has to be installed.
Before you start
MP3 export is built in on Windows and Mac. The manual's LAME FAQ says the patent on the encoder expired, "so now the LAME library for MP3 export is built-in with Audacity for Windows and Mac. Linux users will still need to download and install the free and recommended LAME third-party encoder to export MP3 files from Audacity." If you find a tutorial telling you to download LAME first, check which platform it was written for.
Two things to settle before you open the export dialog:
- Set the Project Rate to 44100 Hz. Audacity's MP3 export FAQ is blunt about it: "The safest solution is to always set your Project Rate to 44100 Hz. Make a rule to check this before you export, because importing a file of some other sample rate may change the Project Rate to that rate." A stray 8 kHz sound effect can drag the whole project's rate with it.
- Do your editing in a lossless format. The manual: "So never do production work in MP3, instead work with a lossless format such as WAV, AIFF or FLAC and for final use then export to MP3."
Also remember what actually leaves the project. Audacity "will only export tracks that are not grayed-out by use of the Mute or Solo buttons in the tracks' Track Control Panels" — a soloed music bed is an easy way to export an episode without its voice track.
The settings Audacity's manual recommends
These five rows come from the MP3 Export Options page, quoted as written:
| Setting | What the manual says it gives you |
|---|---|
| 64 kbps CBR mono | "can give reasonable quality for voice if you are wanting to minimize the file size" |
| 96 kbps CBR mono | "can give excellent quality for voice" |
| 128 kbps CBR stereo | "can give reasonable quality where stereo is required" |
| 192 kbps CBR stereo | "can give very good quality where stereo is required" |
| 256 kbps VBR stereo | "can give excellent quality stereo music, though not recommended for streaming" |
For a talking-head show, 96 kbps CBR mono is the pick — it is the highest setting the manual describes as excellent for voice, and the only stereo entry it calls excellent is a music setting it explicitly warns against for streaming.
Now the part that catches people out. The same page states: "The default MP3 encoding options in Audacity are 170 - 210 kbps VBR (preset "Standard"). While this is a good choice for stereo music, it is not generally recommended for Podcasts." So the box you get by default is the one the documentation steers podcasters away from — you have to change it deliberately.
Mix stereo down to mono before you export
If your voice track is stereo but both channels carry the same audio, the manual says to collapse it first, and gives the reason:
"If you are exporting a constant bit rate spoken word MP3 such as an audiobook and have a stereo track in Audacity where both channels are identical, it is preferable to use Tracks > Mix > Mix Stereo down to Mono to convert to a single mono track before export. This will still sound the same on stereo equipment, but have higher quality because the fixed number of bits have less audio to process."
That is the whole argument for mono podcast delivery in one sentence: at a fixed bit rate, fewer channels means more bits per channel.
Step by step
- Mix down if applicable. Select the track, then Tracks > Mix > Mix Stereo down to Mono.
- Check the Project Rate reads 44100 Hz before going any further.
- Open the dialog with File > Export Audio (Ctrl + Shift + E).
- Choose MP3 from the Format dropdown — the manual's stated route is "File > Export Audio then choosing MP3 from the Format dropdown menu."
- Set Bit Rate Mode to Constant. This is the change that implements the CBR recommendation; the default mode is Preset.
- Pick the bit rate from the table above.
- Set the sample rate. MP3 export offers only three: "32000 Hz", "44100 Hz - default setting" and "48000 Hz". Leave it at 44100 Hz to match the project.
- Set Channels deliberately. In the Export Audio dialog, Stereo is "the default setting even if you only have mono tracks for exporting" — so a mono voice track can still produce a stereo file unless you say otherwise.
- Fill in metadata. For MP3, "only ID3v2.3 tags are exported."
- Export, then play the result back before you upload it.
Try it right here
Runs in your browser. Your file is not uploaded anywhere.
If you already exported a WAV master — which the manual's "never do production work in MP3" advice pushes you toward anyway — you can produce the MP3 as a separate delivery step instead of re-opening the project. The WAV to MP3 converter above runs in the browser tab, which is handy when the machine you are publishing from is not the machine Audacity is on. See all Clapr tools for the rest, and the how-to guides for other export walkthroughs.
Why constant bit rate, when the manual calls it the worst mode
Read the Constant entry on its own and it sounds like a bad idea: "Of the four bit rate modes, this usually gives the worst, least consistent quality for a given file size, but that size itself is completely predictable." The second half is the point. The manual adds: "Use constant bit rate if you are streaming the file over the Internet, as it ensures the audio cannot stutter due to sudden peaks in the bit rate."
Predictable size is easy to reason about too — at "the default rate (128 kbps)", the manual says you get "a known file size of about 1 MB per minute of mono or stereo audio."
One caveat on the Constant entry, quoted as written: "note that if you choose a high bit rate, the LAME encoder may use a lower constant bit rate if you choose 11,025 Hz or lower project sample rate." Another reason to keep the project at 44100 Hz.
Common mistakes
- Leaving Bit Rate Mode on Preset. That gives you 170–210 kbps VBR, which the manual says is not generally recommended for podcasts.
- Assuming 128 kbps is Audacity's default. The MP3 export problems FAQ says "Audacity defaults to 128 kbps bit rate then remembers the last used bit rate if you change it," while the MP3 Export Options page says the defaults are 170–210 kbps VBR. The two official pages differ; the 128 kbps figure is the default within Constant mode. Compare them yourself: MP3 Export Options and FAQ: MP3 export problems.
- Shipping a stereo file of a mono recording. The dialog defaults to Stereo regardless of your tracks.
- Chasing the Extreme or Medium presets by number. The manual describes Extreme as "Extremely high quality" and Medium as "Good sound quality suitable for casual listening or portable devices" but gives explicit bit rates only for Standard and for Excessive ("a constant bit rate of 320 kbps"). For the others, check the official documentation.
- Ignoring the Gain slider. If an export comes back quiet, the FAQ points at the track's "Gain/Volume" slider: "If this slider is over to left, it will reduce or kill the volume in the exported MP3."
FAQ
What bit rate should I use for a podcast in Audacity? Per the manual, 64 kbps CBR mono for reasonable voice quality at minimum size, 96 kbps CBR mono for excellent voice quality, or 128/192 kbps CBR stereo where stereo is required.
Should I use CBR or VBR for a podcast? CBR. The manual states that for podcasts "CBR" is recommended and not "VBR", and elsewhere recommends constant bit rate for files streamed over the Internet because the audio cannot stutter on bit rate peaks.
Is mono or stereo better for a spoken-word episode? If both channels are identical, the manual says mixing down to mono before a constant bit rate export is preferable and gives higher quality, because the fixed number of bits have less audio to process.
Why is my exported MP3 much bigger than the file I imported? The FAQ answers this directly: "this is because the bit rate you exported it at is higher than the bit rate of the original file."
Why does my exported MP3 start with a bit of silence? That is encoder delay, and the manual calls it a limitation of the MP3 format rather than an Audacity bug. See MP3 silence at the start in Audacity for what the LAME info tag does about it.
Settings quoted from the Audacity Manual's MP3 Export Options and MP3 export FAQ pages, checked 16 September 2026. Verify against the current manual before relying on them.
