The secret formula to unforgettable musical hits

Musical theatre has always had a special way of lodging itself in the cultural consciousness; those songs that live long after the curtain falls, cropping up in playlists, singalongs and midnight YouTube rabbit holes. But what exactly makes a show tune unforgettable? That’s the question London Theatre Direct set out to answer in its expansive new study, a data-driven dive into what separates the hummable from the iconic.

The research is an intricate breakdown of 2,136 songs across 100 of the most legendary musicals ever staged from the towering heights of Les Misérables and Phantom of the Opera to modern megahits like Hamilton and Six. It’s a rare attempt to quantify the emotional and structural DNA of the songs that have become not just theatre staples, but global earworms.

“Our research suggests there may be a formula to what makes a musical song work. We found key traits that successful songs share, but there’s no single blueprint for a hit. The best musicals use structure to their advantage while delivering something unique that keeps audiences coming back,” says Ryan Woods, the Commercial Director at London Theatre Direct.

To get to the heart of what makes a stage song land, both dramatically and sonically, the team at London Theatre Direct analysed a range of musical features using Spotify’s audio data. Each track was scored across 10 key traits, including energy, valence, danceability, acousticness, tempo and more. What emerged was a surprisingly consistent profile of the “average” musical theatre song: emotionally mixed, instrumentally rich and built more for contextual flow than for chart domination.

According to the study, the average show tune lands at 51 for danceability, perfect for movement but not exactly club material, while its emotional tone (valence) sits at 43, straddling light and shade. With an energy rating of 39, these songs are more about dramatic nuance than high-octane bursts. They also feature relatively low “speechiness,” suggesting that even the most conversational moments are still wrapped in melody. It’s a recipe that privileges storytelling above all else, designed to carry an audience through a character’s arc without the need for elaborate visuals.

“At London Theatre Direct, we like to think we know a great musical number when we hear one—but is there a pattern behind what makes a song a hit? Our research explores the key traits shared by the biggest musical songs, revealing trends that keep audiences coming back. Is there a formula or just a fascinating coincidence? Take your seats and find out,” Ryan adds.

But when the researchers turned their focus to the 20 most-streamed musical theatre songs on Spotify, tracks like “Defying Gravity,” “Seasons of Love” and “Alexander Hamilton,” a different pattern emerged. These weren’t songs that sat comfortably within the average, they were outliers, bending the formula in very intentional ways.

These hits share a few core traits: memorable hooks, emotionally loaded turning points and a stylistic reach that extends well beyond traditional theatre tropes. Gospel, hip hop and pop all make their presence known, especially in songs that have gone viral or found second lives offstage. The tracks also favour big builds, songs that crescendo into catharsis and a sense of completion that allows them to stand alone, even outside of the story that birthed them.

As Ryan Woods puts it, “There’s a reason certain songs escape the stage and stick with us.” Whether it’s a soaring vocal or a perfectly placed key change, these moments are engineered, consciously or not, to last.

For songwriters, composers and producers, the findings offer more than just trivia. They open a window into how emotional architecture and sonic structure can collide to make something timeless. And for fans, it’s a reminder that theatre has always had its fingers on the pulse of what makes music matter long before the streaming era rewrote the rules.

In the end, the study is a love letter to the power of a perfectly crafted song and whether you’re on stage, in the pit or halfway through your commute, those goosebump-inducing moments aren’t accidents, they’re design.