The answer is a resounding no.
If you’re converting an authorized YouTube audio stream into MP3, choosing “320kbps” will not improve its quality. The ceiling is what YouTube delivers in the first place, not the MP3 settings. (youtube to mp3 320 bit; 128kbps; 192kbps; 320kbps)
What Audio Formats YouTube Actually Streams
YouTube normally streams two main audio formats and one example that was measured. It’s available for most videos but not all. There are also different variations of these formats, with availability dependent upon age and popularity.
YouTube provides the following as a standard:
Format 140: AAC-LC, 128 Kbps stereo, MP4
Format 251: Opus VBR, ~128 Kbps stereo, WebM
A third source measured it at 153k / 135k at 48000Hz.
It also provided a sample of the same video using format 140, AAC, 128kbps, which was measured at 129k at 44100Hz. That’s just over 128kbps, but it’s still in the same ballpark.
Why YouTube to MP3 320 Bit Cannot Beat the Source
One independent analysis found the source material itself already missing detail before any conversion. In that measured example, the AAC 140 output was cut off just under 16kHz, and the Opus 251 output removed content above 20 kHz. One author notes that more examples are needed to generalize from this.
A 320kbps MP3 cannot improve on that source. A higher output bitrate cannot restore details that were missing from the source. In fact, encoding to a higher bitrate won’t produce a file that is better than the original, either. (Higher output bitrate ≠ better source audio; no sounds added that weren’t there)
When a Higher Bitrate Matters
There’s only one real reason a higher bitrate matters.
Converting a lossy stream to MP3 is lossy-to-lossy, and adds its own loss, which is best avoided when possible. Forum contributors say that a slightly higher target only limits that extra loss, and recovers nothing. YouTubeToolkit describes higher bitrates as less aggressive compression, so YouTubeToolkit would suggest that increasing the bitrate minimizes further loss, though they say YouTubeToolkit doesn’t recover anything from that.
File Size at 320kbps vs 128kbps
YouTubeToolkit has published a file size guide for various bitrates and pairings. Weigh whether or not the 320kbps setting’s roughly 2.5x size is worth it against a ~128 Kbps source. For instance, a four-minute file @128kbps takes up about 3.8 MB; 320kbps uses ~9.6MB, which is 2.5x larger.
Here’s how others have used them:
MP3s can range from 64kbps (voice) and 128kbps (podcasts, interviews and casual listening, per YouTubeToolkit) to 192kbps (a balance between music and everyday listening), up to 320kbps, described as the highest standard MP3 bitrate, with the largest files. 192kbps should be sufficient for nearly everyone else.
You might find 320kbps described as the highest standard MP3 bitrate. As noted, MP3 stays lossy, so a 320kbps file made from a lossy YouTube stream is neither lossless nor studio quality.
Converter Claims About Studio Quality
Some converters tie 320kbps to studio-quality results. Flvto says that choosing up to 320kbps gets you the “closest thing to the original studio quality.” CnvMP3 offers 96, 128, 256, and 320kb/s options, but again, YouTubeToolkit warns that 320kbps cannot restore any lost quality, regardless of how you try to convert it.
Free YT to MP3
The site Free YT to MP3 is pretty straightforward. Paste a link, convert to MP3, download on the same page. No bitrate selector appears to be documented, nor does it appear that any particular bitrate is claimed. Convert only content that you own, have permission for, or that is licensed for download — since personal use alone doesn’t make it permitted. You’ll need to watch YouTube’s terms carefully to ensure that your use isn’t prohibited.