Iron Maiden's happiest songs were released in the 80's and 90's. Anyone who has listened to the most popular metal band ever probably knows — and enjoys — tracks like Aces High, Running Free, Wrathchild and The Trooper, among the happiest songs ever created by the band. After the 2000's, the band became sadder, like in The Reincarnation of Benjamin Breeg or The Great Unknown.
This is the conclusion of an analysis using Spotify API data from every studio album (excluding live albums and singles), based on the "valence" of each song. According to Spotify, valence is a measure from 0.0 to 1.0 describing the musical positiveness conveyed by a track — high valence sounds happy, cheerful, euphoric; low valence sounds sad, depressed, angry. Lyrics are not considered.
Disclaimer: This is not science. It's a data analysis project for the Master of Science in Data Journalism at Columbia Journalism School. I'm a fan of the band and play in a metal band myself. Read the full code and data analysis here. You may need to create your own Spotify keys to run it.
Every song's happiness score, by year of release
Each dot = one studio song · Color from ■ red (sad, valence → 0) to ■ gold (happy, valence → 1) · White line = yearly average · Hover for song names
Powerslave: The Happiest Unhappy
Released in 1984, Powerslave is the happiest Maiden album ever — but even at its peak it barely crosses the 0.5 mark. In Spotify's world, that still makes it a "sad" album. The classic era (1980–1992) dominates the top half of the valence rankings, while post-2000 albums fill the bottom.
All studio albums ranked by average happiness
Average album happiness from 1980 to 2021
Each dot = one studio album. Hover for details. The peak at Powerslave (1984) and the cliff-drop after Fear of the Dark (1992) are unmistakable.
Top 10 Happiest Songs
By reviewing the songs separately, a few could make Eddie smile — all released between the 80's and 90's. Notice that even the happiest song ever, Wrathchild, tells the story of a young man searching for his unknown father.
Top 10 happiest songs — valence score
Hover a bar for album details. All 10 songs are from the classic era (1980–1998).
Song spotlight — #1 happiest
Wrathchild — Killers (1981)
Ironically, the happiest Iron Maiden song tells the story of a young man searching for his unknown father. Listen to that driving, upbeat chorus and then compare it to the sadder songs below.
Top 10 Saddest Songs
The top 4 saddest songs — Lord of Light, Hell on Earth, The Great Unknown and Isle of Avalon — were all released after 2006. Though there are also six songs from the 80's and 90's on this list, the dominance of recent albums at the bottom is undeniable.
Top 10 saddest songs — valence score
The shorter the bar, the sadder the song. The top 4 are all post-2006 — the modern era.
"Even at its happiest, Iron Maiden barely crosses the halfway mark on Spotify's positiveness scale."
Songs Are Getting Longer
It's not just that Iron Maiden songs are getting sadder — they're also getting dramatically longer. The average song on Killers (1981) runs under 4 minutes. By The Book of Souls (2015), the average is over 8 minutes. Empire of the Clouds, from that album, clocks in at a staggering 18 minutes.
Fun fact: 48 of their 162 studio songs run longer than 7 minutes. That's nearly 30% of their catalog classified as "epic" length — longer than most full pop songs today.
Average song duration per album (minutes)
The Minor Key Takeover
In music theory, minor keys sound darker and more melancholic. Major keys sound brighter and more upbeat. This perfectly mirrors the valence trend — as Iron Maiden's songs got sadder, they also shifted massively toward minor keys.
On Killers (1981), only 10% of songs used minor keys. By A Matter of Life and Death (2006) and Senjutsu (2021), that number reached 90%. The band's harmonic language changed completely.
Percentage of songs in minor keys per album
"On Killers (1981), 10% of songs used minor keys. On Senjutsu (2021), 90% did."
Spotify Audio Features AnalysisThe Mood Matrix: 4 Types of Iron Maiden Songs
Using valence (happiness) and energy together, every Iron Maiden song can be classified into one of four emotional categories. The results reveal how diverse their catalog really is — even if "sad" dominates.
e.g. Aces High, Wrathchild, Running Free
e.g. Phantom of the Opera, Montségur
e.g. Lord of Light, Hell On Earth
e.g. Journeyman, The Clansman
The dominant category — Happy + Energetic — includes the classic hits most fans love. But Sad + Mellow and Sad + Energetic together make up 54% of the catalog. Over half of Iron Maiden's songs are sad, whether fast or slow.
How Happy Is An Average Concert?
Let's take a look at how a full concert would look in terms of happiness. This chart is based on an "average setlist" containing the most common song sequence for their shows in 2019. (No 2020–2021 data due to the pandemic.)
Emotional arc through a typical 2019 concert setlist
11 songs from the Legacy of the Beast Tour 2019 average setlist. Hover dots for song names. The concert opens with a rush, then tumbles into the band's darkest territory.
Does Sadness Drive Popularity?
So why are there so many sad songs? Do people enjoy sad songs more than happy ones? Spotify's "popularity" score (0–100) shows how popular a song is at any given moment.
There isn't really a pattern. 8 of their 20 most popular songs are sadder than the band's average. 12 are happier. When we calculate the correlation across all songs, we find a very small relationship. Maybe we should just ask the fans.
20 most popular songs — Spotify popularity score (color = happiness)
Bar length = Spotify popularity (0–100). Color from ■ red (sad) to ■ gold (happy). No clear pattern — fans love both sad and happy songs.
Can You Dance to Iron Maiden?
Bonus finding: there's just one song that is remotely suitable for dancing — and Iron Maiden fans hate it.
Danceability anomaly
The Apparition — Fear of the Dark (1992)
At 0.592 danceability, The Apparition stands far apart from the rest of the catalog. Some fans call it "easily their worst song." It has never been performed live — not once in over 30 years.
Top 20 songs by danceability score — The Apparition is in another league
Danceability score 0–1. The Apparition (0.592) is the clear outlier — every other song is below 0.48. Note the gap between #1 and #2.
But if you really want to dance, try this mega funk version of The Trooper: