Methodology
How the Power Index works
The Power Index scores an artist from 0 to 100 on how strong their market position is right now. It blends three scores, weights them for the artist's market, and carries a confidence rating so a score built on thin data is never read as firm.
The headline score
The Power Index is a weighted blend of Reach, Engagement and Momentum. Momentum runs from -100 to +100, so it is converted to 0 to 100 first, which means a steady artist reads 50 on it and is neither rewarded nor punished.
Reach
45%
0 to 100
How many people the artist actually reaches.
Engagement
35%
0 to 100
How deep and real the connection is.
Momentum
20%
-100 to +100
Which way the numbers are moving, and how fast.
The tier beside the score is set by Reach: Top-tier at 70+, Mid-tier from 40 to 69, Developing from 15 to 39, and Emerging below 15.
Reach
Reach is built from listeners, streams, followers and views across every platform we have data for. Each number is placed on a logarithmic scale against a world-class benchmark for that platform, because artist sizes span six orders of magnitude and a straight scale would let the biggest numbers drown out everything else. A number at or above the benchmark scores 100.
Platforms are then weighted for the artist's market. We use a sourced country profile where we have one, a regional profile where we do not, and a global default otherwise, and the weights are re-balanced across only the platforms with data, so a missing platform never drags the score down.
View counts are discounted
Views are the easiest number to inflate, so they count at a fraction of face value.
YouTube 40% · TikTok 50%
Stale followers count for less
A follower base that is shrinking or flat is weighted down; one that is growing is weighted up, capped so a single month cannot override it.
0.7x to 1.15x
Features are kept out
Reach from songs the artist is featured on appears as its own layer, not in the headline.
Shown separately
Engagement
Engagement measures depth, not size. Each action is weighted by how hard it is to fake, so paid support counts for far more than a like.
Paid support
Audiomack supporters, Apple Music purchases.
1.00
Listening time
Spotify super-listeners, YouTube watch time.
0.85
Shares and discovery
TikTok sound uses, Instagram shares, Shazams.
0.70
Editorial placement
Radio and algorithmic spins.
0.60
Saves and playlist adds
Spotify saves and playlist adds, Instagram saves, Boomplay fans.
0.55
Comments
YouTube and Instagram comments.
0.40
Likes
Instagram likes.
0.20
On top of that ladder, four signals can add a capped bonus. They are capped because each says how engaged an audience is but not how large it is, so none of them can set Engagement on its own.
Measured engagement rates
TikTok, SoundCloud and YouTube engagement rates, judged against what is excellent for an artist of that size. The bonus is shared across the rates present, so being on more platforms earns nothing by itself.
up to +10
YouTube comment rate
Comments per million views on the artist's own channel videos.
up to +12
Deezer playlists
Only playlists the artist is confirmed to be in, with at least 1,000 saves, weighted by position.
up to +12
Spotify fan playlists
A lighter signal, kept small because it is matched by name.
up to +8
A low Engagement score often means we do not have deep engagement data yet, not that the audience is disengaged. The confidence rating says which it is.
Momentum
Momentum is the direction and speed of the artist's numbers. With 3or more snapshots it is the slope of a line fitted through the recent history, so one odd week does not swing it. With fewer, it falls back to the change between the last two readings and is marked as less reliable. Any single signal's change is capped at ±200% so a first viral spike cannot dominate for good, and follower counts earn half credit because they grow slowly by nature. A brand-new artist shows a dash until there is enough history.
Confidence
Every Power Index carries a confidence rating from 0 to 100, so you know how firm the number is.
Coverage
How many signals back the score. Full marks at 8.
50%
Verified share
How much comes from trusted sources. An account the artist has connected counts in full, a platform feed at 0.9, an aggregator at 0.8, and a hand-entered number at 0.35.
35%
Trend reliability
How cleanly the history fits a trend.
15%
70+ reads as high confidence, 45 to 69 as moderate, and anything lower as provisional.
Full Market Power
Beneath the headline, the breakdown shows the wider picture. True Audience is live today: the artist's unique real fans across platforms, after removing bots, dormant followers and the same person counted twice, plus the superfan core. The other dimensions (Virality, Cultural Capital, Crossover, Earning Power, Commercial, Audience Quality and Consistency) show as "Soon" and light up as their data sources connect. They do not change the Power Index.
Where the data comes from
Spotify
Monthly listeners, followers and streams, plus the artist's own account when connected.
YouTube
Subscribers, views and per-video engagement, read from the artist's own verified channel.
Audiomack, Deezer, Last.fm
Plays, followers, fans, supporters and verified playlist data, from each platform's API.
Songstats
TikTok, Instagram, SoundCloud, Amazon Music, TIDAL, Shazam and measured engagement rates.
Apple Music
Entered from Apple Music for Artists until API access is available, at reduced trust.
Snapshots
Collected daily and stored with a date, which is what Momentum and confidence are built on.
Frequently asked questions
Why is Reach weighted the most?
The Power Index answers one question: how strong is this artist's market position right now? The size of the audience they command is the backbone of that, so Reach carries 45%. Engagement carries 35% because it is the quality check on reach and the hardest part to fake. Momentum is 20%: it is useful, but it moves week to week and is the easiest to inflate, so it tilts the headline rather than driving it.
Why does a steady artist not score zero on Momentum?
Momentum runs from -100 to +100 and is converted to a 0 to 100 scale before it is blended, so flat reads as 50. A steady artist is neither rewarded nor punished; growth lifts the headline and decline lowers it.
What does the confidence rating mean?
It tells you how much to trust the score, from 0 to 100. It blends how many signals we have (50%, full marks at 8 signals), how much of the data comes from verified sources rather than hand-entered numbers (35%), and how clean the growth trend is (15%). 70+ is high confidence, 45 to 69 is moderate, and below that the score should be read as provisional.
Do features count towards the score?
No. The headline is built from the artist's own catalogue. Reach from songs they are featured on is shown separately as "added reach from features", because it lifts the numbers while the song runs but you cannot run a campaign on a track you do not own.
Are the numbers weighted for my market?
Yes, for Reach and Momentum. Each platform's weight depends on the artist's primary country: a country profile where we have sourced one, otherwise a regional profile, otherwise a global default. An artist is never punished for a platform they have no data on; the weights are re-balanced across the platforms that do have data. Engagement is not market-weighted, because it is weighted by how hard each action is to fake instead.
How often is the data refreshed?
Platform numbers are collected automatically every day and stored as dated snapshots, which is what lets Momentum measure a trend rather than a single reading.
Can a score be gamed?
It is built to resist it. Views are discounted before they count (YouTube views at 40% of face value, TikTok views at 50%), follower counts lose weight when they stop growing, and Engagement counts paid support and listening time far above likes and follows. Bought followers without real listening show up as high reach with thin engagement.
Is the public Star Power the same score?
No. Star Power at rosterapp.ai/star-power is a separate public product that scores any artist from public data on one worldwide yardstick, with no market weighting and no engagement figure. The Power Index is the fuller read on the artists you manage, built on connected accounts and history.