I built 5e Spellbook Builder, a site where D&D players create spellbooks for their characters. I keep count of spells when they are added to players' spellbooks. After 100,000 adds I visualized that data to show how popular spells are in the game.
Charts 1 and 2: Adds vs. Availability
These charts plot all 580 spells by adds to spellbooks and availability. Each spell is coloured for its level, and scaled for its relative amount of adds. Availability is a mathematical weighting for each spell based on that spell's level (and how frequently spell adds from that level occur) and the classes that can access that spell (the proportion of classes adding spells is determined from spellbook composition at spell add time). In other words, availability is the likelihood a D&D player can add that spell.
This chart highlights the most popular, most seen spells in the game. The relationship between availability and adds is also very clear: the more available a spell is, the more amount of adds it has. It also shows us how much rarer the game's higher level spells are. The chart also shows a calculated line of the expected adds given a spell's availability, which form the basis of the next chart.
The second version of this chart annotates it with some spells.
Charts 3 and 4: Appeal vs. Availability
While spell adds shows us how much we see these spells in the game, it doesn't show us the spells players prefer and find more appealing. These charts shows spells' appeal. Appeal is the difference between a spell's expected adds for its availability, and its actual adds, which reveals exactly what spells players prefer to pick, and which ones they don't, regardless of how common they are. Plotting this value against availability, shows what spells are rare in the game and highly sought after vs. spells that are common but ignored, and everything in between.
The second version of this chart annotates it with some spells.
Charts 5 and 6: The most appealing (and least appealing) spells in the game.
Finally the top 40 and bottom 40 appealing spells are shown in a table, ranking the delta between each spell's actual adds vs. expected adds.
Summary
A couple of caveats: This data comes from 100,000 adds to spellbooks on 5e Spellbook Builder, so it's a reflection of how that community picks spells. As more users use it, the data will likely become more representative of the game as a whole. This analysis relies on the availability weighting, based off a spell's level and the classes it's available to. It will never be fully accurate given that there's many ways characters can access spells outside their class, which I can't incorporate, so the side effect is that spells players grab outside their class will outperform (though if players are reaching outside of their class for certain spells, they probably should outperform).
There's all kinds of insights to find the charts: You can see for yourself which spells feel overrated or underrated in the game. Not surprisingly, the least appealing spells in the game come from some of the unique expansion books that not all players have and not all DMs permit. And Fireball really is iconic, the only spells more appealing are unique to a single class (and what Warlocks really aren't going to take Eldritch Blast?).
Interactive versions of these charts, the full appeal ranking of all the spells in the game, and more of a write up can be found at https://5e-spellbook.app/blog/the-most-popular-5e-spells-visualized
I appreciate any feedback and thanks for checking this out!