Six thousand two hundred and ninety one. That was the number of genres one man at Spotify had named, mapped and stocked with artists by the time the company let him go in December 2023 and his map stopped moving, and buried inside it, under labels as fine as epic black metal and technical brutal death metal, sat metal in more shapes than any one fan could name. The data engineer who had spent a decade teaching machines to tell two hundred and two kinds of folk apart was Glenn McDonald, and his map, Every Noise at Once, is the largest answer ever given to the question of how many metal subgenres are there. It is not the right answer. It is only the biggest.
A tea bush gives the same leaf it has always given, and the leaf goes the same way, crushed, torn and curled between steel rollers until its cells split open, then dried, sacked and sent to the auction room. There the tasters stand at a long bench, slurp each cup hard enough to spray it across the tongue, spit it into a spittoon and write down what they found, and every newcomer at the bench wants a word his neighbour has not used. The list of named flavours lengthens every season. The bush has not changed. The tasters have multiplied.
Metal is counted the same way. The records are already pressed, and what keeps rising is the number of people paid or driven to describe them, each of them reaching for a name the last one did not use. Which line each branch broke along, and when, is set out where it sits in the story. The count is a separate trade, and four very different hands keep it.
How many metal subgenres are there, and who does the counting
The Intel programmer who started Discogs from a server in his apartment closet in 2000, as a catalogue of the electronic records he owned, was Kevin Lewandowski, and the database he built files every release under a closed list of styles that its editors extend only rarely. A metal album there is filed under one of a fixed shelf of named styles, Heavy Metal, Speed Metal, Doom Metal, Thrash and their neighbours, whatever the band believes it plays. The record shop had fewer boxes still. A rack is made of wood, and floor space costs rent.
At the far end sit the encyclopaedias that leave the genre field as free text, written band by band, where the number of distinct descriptions has no ceiling at all. Between the two stands the machine. It never asks the band anything. It watches who listens to what, draws a border wherever the listeners bunch together and prints a name on the border, which is how one map came to hold epic black metal and deep symphonic black metal as two separate countries.
| Who counts | How a name gets in | What the count looks like |
|---|---|---|
| A record shop rack | Floor space and what sells | A handful of dividers |
| Discogs | A fixed style list, extended by the site's editors | A fixed shelf of named metal styles |
| Metal Archives | Free text written for each band | No ceiling |
| Every Noise at Once | Listening data clustered by an algorithm | 6,291 genres of every kind, frozen at the end of 2023 |
All four are honest. No two of them agree. The shop measures what it can sell, the catalogue what it can file, the encyclopaedia what the bands say, and the algorithm what the listeners do, and each figure is exact about its own question and useless for the next one.
Metal has fanzines, labels and algorithms, every one of them free to add a name and not one with the power to strike a name off.
Four ways a new name gets made
The first is the calendar. A revival gets a wave named after it, and the wave becomes a subgenre built out of a date rather than a sound, which is how the new wave of traditional heavy metal came to be written on flyers by the mid to late 2000s for young bands playing the rules of 1983.
The quartet formed in the Swedish town of Arvika that fired "Undying Evil" off From Beyond, released by Nuclear Blast in February 2015, a gallop hammered flat and a scream thrown over it at full stretch, was Enforcer, and nothing in its sound needs a name the British bands of 1980 did not already carry. It needed a name anyway. The listeners wanted the new records kept apart from the old ones.
The second is geography applied after the fact. The New York band whose 1988 album Thundersteel now heads most lists of US power metal was Riot, and critics stuck the label on after the fact, once German bands had claimed the words power metal for a brighter sound and the older American style needed a name of its own to be told apart.
The surviving members renamed the band Riot V in 2013, after the death of its founder, Mark Reale, and it still plays the title track live, a song that runs a speed metal riff under a voice climbing clear above the guitars and that had no idea, when it was cut, that it was founding anything. A subgenre can be handed to a record twenty years after its release. It rarely asks permission.
The third is the slogan. The quartet that printed Death to False Metal on the sleeve of 1983's Into Glory Ride and turned it into a battle cry was Manowar, and on German metal sites true metal hardened from a boast into a genre category of its own. A sect with a catechism of leather and swords. A rack of its own.
The fourth is the prefix. Blackened, melodic, symphonic, technical, progressive and post can be bolted onto almost any root, and five prefixes on ten root styles make fifty names before a single band has recorded a note under any of them. The algorithm added a sixth prefix of its own, deep, for the listeners further from the centre. The stock never runs out.
Why the count only ever rises
A coral reef grows on its own dead. Each polyp builds a limestone cup, dies inside it and leaves it as the floor for the next, so that the reef climbs for thousands of years without ever subtracting a thing, and the first a skipper learns of how far it has come is the shriek of his hull tearing open on a ledge that was not there when his grandfather sailed the passage. Genre names build the same way. A style that stops recording leaves its name behind as the floor for the next, and nobody has the authority to chisel it out.
Sport has federations that can abolish a category between one season and the next. Metal has only its vanguard of fanzines, labels, press officers and algorithms, each free to add a name, none with the power to strike one off, and every name has progeny the moment it lands: once melodic death metal existed, melodic black metal was one word away, and melodic doom one word after that.
The market pushes from behind. A label with a young band to sell needs two words that tell a buyer what the record sounds like, a streaming service needs a label on every playlist, and a scene that has put out three good demos wants a name of its own before anyone else hands it one. None of them is lying. All of them are adding.
A count worth keeping
Most of the names measure something other than the music. A new decade, a new town, a new costume or a new slogan changes the filing and leaves the riff where it was, and a name that changed nothing on the record is a divider in a rack, attested by nobody but the man who printed it. The count that means anything counts what happened to the sound: a new tempo, a new tuning, a new use of the voice.
The thing that hath been, it is that which shall be; and that which is done is that which shall be done: and there is no new thing under the sun.
Ecclesiastes 1:9, King James Version
Counted that way the number falls to something a fan can hold in one hand and a spare finger or two, and the argument moves on to a harder question, which of those changes weighed the most. That weighing is a separate job, and it is done in the metal subgenres tier list, one test at a time.
So the honest answer to the question has two parts. As many as anyone cares to name, and the list will be longer next year. Far fewer that ever moved a riff.
