# My Totally Unscientific Spotify Bitrate Calculation



## mcmoyer (Oct 22, 2018)

So I've spent a lot of time comparing the native Spotify client with streaming Apple Music via Bluetooth. It's really a toss up to my ears. In summary, Spotify seems to have tighter bass at times, but then again it sometimes sounds a bit harsh overall to me. Apple Music seems to have a bit muddier bass, but it's not something I would notice I was wasn't specifically looking for it.

Today, though, I had some unused PTO that I needed to burn. I realized halfway through the day that I had the internet connection all to myself so it was prime time to do some experimenting. I have a SNMP endpoint that will tell me transfer rates and total transfers, up and down. I went to my car and brought up a playlist on Spotify that I had never listened to before and was based on recent music.










I reset the totals on my SNMP monitor to zero and then played the first 5 songs, waiting about 30s on each song, on that playlist. And then looked at the totals










17.1 MB, but I do have residual traffic on my network so I timed 4 minutes of traffic without downloading any songs










About 2.5 MB over ~4 minutes which is about the time it took to do this test...I did say that this was totally unscientific.

Altogether, the songs add up to 16:18 or 978 seconds

(17.1 - 2.5 = 14.6 MB) / 16.3 min = 0.895 MB/min...but let's round that up to 0.9 to make it even less scientific

I mentioned earlier that I have Apple Music and my CD library was encoded at 256kbit so I started checking my library. Billy Joel's "This is the time" runs 5:02, the file size on my computer is 9.9MB. Blue Man Group's "Piano Smasher" runs 3:01 and weighs in at 6.9MB. Dire Straits' "Brothers in Arms" runs 6:59 and takes up 14.3MB. So roughly 2MB per minute or so.

My conclusion...Spotify is running around 128 kbits

I used this site to corroborate the files sizes for different bitrates as well 
https://www.colincrawley.com/audio-file-size-calculator/


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## MelindaV (Apr 2, 2016)

mcmoyer said:


> My conclusion...Spotify is running around 128 kbits


and how does Slacker compare based on your test protocol?


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## Johnston (Oct 12, 2018)

MelindaV said:


> and how does Slacker compare based on your test protocol?


Interested as well in how Slacker compares.

Also, does your estimation take into account songs are usually downloaded ahead of time to prevent buffering? Would that effect your results?


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## mcmoyer (Oct 22, 2018)

I used the "Top Hits" station on Slacker and played 5 songs from that for a total of 16:13s and a total of 13.1 MB transferred. That comes out to around around 0.8MB/min


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## mcmoyer (Oct 22, 2018)

for a control (lol, on this totally unscientific test), I played "The Eternal Remixes" from U2 on my iPhone straight from the Apple Music suggestions. 4 songs that clock in a 16 minutes and the total downloaded was 43.5 MB


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