Undertone help & support
Contact: our contact page — we usually reply within a few days.
Frequently asked questions
How does Undertone know a song's mood? An AI model judges each song from what it already knows about it — its sound, tempo and what it's about in general. It doesn't listen to the audio. For songs it doesn't recognise, the song shows "Best guess".
What do the moods mean? There are ten: Joyful (happy, feel-good), Energetic (hype, driving), Confident (bold, swaggering), Romantic (love, devotion), Calm (peaceful, gentle), Dreamy (hazy, atmospheric), Nostalgic (bittersweet, looking back), Sad (heartbroken, low), Angry (aggressive, defiant) and Tense (anxious, dark).
What are "positivity" and "energy"? Positivity is how upbeat or down a song feels. Energy is how calm or intense it is. The timeline shows both across the playlist in order.
How do I use a Spotify or Apple Music link? Open the playlist in Spotify or Apple Music, tap Share (or •••), then Copy link. In Undertone, tap Paste a playlist link and then Paste. If you've just copied a link, the Home screen offers to paste it. You'll see the songs to check before anything is read.
"This Spotify playlist can't be read." Playlists made by Spotify itself (like Today's Top Hits, Discover Weekly or Daily Mix) and private playlists can't be opened by other apps. Try a playlist you made and made public, or use screenshots of the playlist.
"That playlist is private" (Apple Music). Links that start with music.apple.com/library/ open only for their owner. On Apple Music, share the playlist publicly (your profile › Show on My Profile), then copy the link again.
A playlist link only brought in some songs. Undertone reads up to 200 songs at a time, so it takes the first 200. Items that aren't songs — podcast episodes or music files stored on someone's computer — are left out, and the review screen tells you how many.
What formats can I paste? One song per line: "Artist – Song", "Song by Artist", numbered or bulleted lists, or a CSV/TSV exported from a music app (the columns are found by their names). If a line has no artist, the review screen asks you to add it.
My screenshot didn't find every song. Use screenshots of the song list itself, not the Now Playing screen. You can pick up to 10 at once; songs that appear in two overlapping screenshots are only counted once. You can fix or add songs on the review screen before reading.
Apple Music says there are no playlists. Turn on Settings › Apps › Music › Sync Library, then try again. If you turned off access, turn on Media & Apple Music for Undertone in Settings.
Is there a limit? Up to 200 songs per reading, 20 readings a day and 60 playlist links a day. The counts reset at midnight UTC. Reopening a saved reading — or reading the exact same list again — doesn't count.
Where are my readings saved? Can I delete them? Only on your phone. Swipe left on a reading in "Your readings" to delete it, or use Settings › Delete all readings.
Does Undertone use Spotify? Only when you paste a Spotify playlist link: our server then reads that public playlist's song names from Spotify. You never sign in to Spotify. "Find on Spotify" just opens a search for the song.
What's sent to the AI? The song, artist and album names in the list you read, and the playlist name. For songs the AI doesn't know well, our server adds a short lyric snippet (a line or two) from LRCLIB or Genius. Lyrics are never stored or shown. See the privacy policy for details.