The purpose of this site is to take several Spotify Playlists and generate a single playlist from them.
The system then monitors those lists for changes and propagates any changes to the master list. This means that you can now follow spotify created lists or user created lists that change frequently to make your own mix in a single list. Ideal for mobile users. Can also be used to merge Spotify playlists!
Your privacy is important to us so we wanted to outline exactly what we store and how we use it. Here is the list:
  • Your username and an authentication token that allows us to modify your playlists. This is obtained as part of the o-auth process and is provided by spotify. This does not give us your password or any account information. We also store the time this was last successfully obtained. Only recently did Spotify start telling users exactly what the app they are authenticating to is requesting access to, but here are the technical scopes that we request access to anyway:
        [0] => playlist-read-private
        [1] => playlist-read-collaborative
        [2] => playlist-modify-private
        [3] => playlist-modify-public
        [4] => ugc-image-upload
  • A list name, and spotify id for the primary master playlist. We also give this list a unique id that we can match to later. This is so that we know which list to modify. We also store a date/time of the last time this list either 'gained' or 'lost' any tracks. This helps us determine how 'fresh' a list is. We try not to refresh a list that has changed in the last 20 minutes to avoid spamming the spotify servers.
  • The playlist id and owner id of each list you want to add to your master list . We also store the associated id from the previous step so that we know which list is the master for each sub list.
In short, no. Excluded lists are explicitly excluded from ever being included. It's a sort of blacklist. Imagine you include a Spotify curated Top 50 list that has some songs you don't enjoy. If you created a list of your own that contained the songs you never wanted to appear on your Master List, then excluded that list from your Master List, the script will only add the songs that do not appear on your excluded playlists.
The only limit that currently exists is the number of songs that will be added to a master list. To limit the number of hits to the spotify api per user, we only add the first ~7500 songs that are found on a scan. Because of the way we hit the spotify api though, they give us chunks of songs back and we only stop requesting additional songs after we hit 7500 so occasionally they might give us a few more than that number. We might add the ability to increase this limit in the future for paid accounts, but at this time only donations are accepted. All accounts are treated equally.
Those numbers in the last update section of the graphic are what the script did to your track count last time it updated your master playlist. It will show the last date that it updated (according to UTC) and how many songs were added or removed. In this example there was 20 songs added and 3 removed. Now you know when the last time the master list was updated and by how much :)
Thanks for asking such a non-scripted question! As a part of using this service there are certain conditions that you agree to as outlined in the privacy policy and terms of use documents linked in the footer of this page. There are some additional terms as outlined here. By signing in, and authorizing this app on your Spotify account, you hereby provide your agreement to the following:
  • We do not make any warranties or representations on behalf of Spotify and we expressly disclaim all implied warranties with respect to the Spotify Platform, Spotify Service and Spotify Content, including the implied warranties of merchantability, fitness for a particular purpose and non-infringement
  • You agree that you are prohibited from modifying or creating derivative works based on the Spotify Platform, Spotify Service or Spotify Content
  • You are prohibited from decompiling, reverse-engineering, disassembling, and otherwise reducing the Spotify Platform, Spotify Service, and Spotify Content to source code or other human-perceivable form, to the full extent allowed by law
  • WritheM Web Solutions is responsible for this app and we hereby release any liability on the part of third parties (e.g., Spotify); In short, Spotify is not responsible for the content found on the WritheM Servers.
  • Finally, Spotify is a third party beneficiary of the WritheM end user license agreement and privacy policy and is entitled to directly enforce our end user license agreement on our behalf
As part of our agreement to access the Spotify Servers we agree to some conditions. One of which is to delete all information on our server if you revoke access to the app. To revoke this app from accessing your account going forward you can go to your Spotify Account Settings -> Click Apps and then click the Revoke Access button next to IntelliMerge for Spotify. A direct link to this page is here. Once we detect that we no longer have access to your account we put your account on hiatus until you sign back in via the web browser and re-authenticate the app. If your account stays in a hiatus status for 60 days, we remove all records of your playlists and the associations you made on the IntelliMerge for Spotify app. If you wish to manually reduce this wait period to zero, you can email our support or use our contact form and ask for manual account deletion. You will also need to provide us with your Support ID which can be found at the bottom of the playlist editor here to verify the ownership of your account.
This is an inexepensive project that has been endorsed and supported by WritheM Web Solutions. We provide this as a free service to you, but any donations you would like to make would be appreciated! You can send us pennies via paypal, or click this button.

Here is a copy of the updates as they were originally posted on the main page. Each named version is included below.
We are currently running version: imfs-1.1-20200108

08 Jan '20: v1.1-"Algernon"
  • I've had to reduce the frequency that we check for updates. We're just too darn popular! We currently have 3 instances of the generate script running at any time so to reduce the number of hits to the spotify servers we now only check your playlists once each hour. Thanks for your understanding :)
  • To increase efficiency in the incrimental generation script I've moved the purge function to the cleanup process which only executes once a day instead of every 10 minutes. Users who need to be purged will via a separate process that runs once a day.
  • I've also added a bit of additional debug output to help isolate a duplicates glitch that was reported late last year. Updates likely to follow in the next minor version.
11 Jun '19: v1.0-"Kokiri-Forest"
  • Welcome to 1.0.
  • You can now blacklist a set of songs with the exclude feature. Check the About/FAQ for full information
  • I have added the ability for you to decide if you want the script to update your cover-art on a per-playlist basis.
5 Jun '19: v0.9-"Lemon-Squeezy"
  • It is super basic but I've started to work on a theme. This means that the app will fully respect mobile devices and their screen sizes. Things should look much better for mobile users.
  • I am aware that some users have url's in their magic playlist's description. For those users the script is currently double escaping the /'s in the url and making for a messy display after a few runs: "&#x2F". The only solution I have right now is that you dont use urls in your playlist's description. It's not clickable anyway, so I urge you to consider it's importance anyway. :/
30 May '19: v0.8-"🐛"
  • Was updating the playlist log but not sorting it. Now it sorts by date. Most recent at top. Which means the cover art now shows the last time it was udpated, not the first time. Thanks to Martjin for reporting.
  • Playlist descriptions are respected if there is one. A '#log' is appended for the last 5 days at the end of the description.
5 May '19: v0.7-"Rembrandt"
  • New functionality: The script will now update the cover art and description with a short log of when it added/removed anything. Some users may need to re-oauth for the cover-art to work. TODO: Will add a way to choose if you want the cover art replaced in the future. Dates are based on UTC.
  • A limit has been added of maximum 7500 songs in a single magic list. If more songs are gathered, only the first 7500 songs will be added.
  • I was previously detecting purged accounts based on ANY error from spotify when refreshing the oauth token. I am now properly capturing and purging only instances of token's being revoked on Spotify Accounts. The script will only purge revoked accounts now :) Sorry for anyone who was erroneously purged :( Feel free to use the import feature that I've added to re-add. Shouldn't happen again though.
10 Dec '18: v0.6-"Brutus"
  • We are just starting to generate updates again after a month of being offline. Thank you for baring with us. We have optimized the script and it should run smoother than ever. Check for updated information
26 Nov '18: v0.5-"Caesar"
  • Recently went through some major server upgrades that did two things... Made things run faster, and did not migrate data. Sue me. You don't pay me. Okay don't sue me... please. I this for free. That being said, users will need to reauthenticate and then recreate their magic playlists. Sorry about that :( Should be generating lists again soon.
13 Jun '18: v0.4-"Reassignment-Surgery"
  • Fixed some assumptions on data-types.
27 May '18: v0.3-"Echelon"
  • Was getting some spotify api errors. The script catches those now and skips the problematic entry if anything dies. Additionally I output the errors to a log file so that I can analyze the problems later. The file deletes at the start of every day at midnight. Should allow me to fix the problem that Spotify is throwing...
30 Apr '18: v0.2-"Owlet"
  • First public version.

Show me some cool stats?

Alright. We dont have a lot of data but:
  • We monitor lists for 913 accounts.
  • These users have 694 master lists.
  • And requested that we monitor a total of 8507 playlists for changes.
And some specific technical stats on our last run:
  • last_add=>11380
  • last_black=>13915
  • last_del=>14
  • last_mpls=>77
  • last_users=>78
  • total_add=>30325107
  • total_del=>4450060
  • total_mpls=>1150
  • total_runs=>101882
  • total_tracks=>71534
  • total_users=>913
  • time_complete=>2020-02-19 23:00:18 UTC
  • time_current=>2020-02-19 23:06:41 UTC