Volcanodle
A daily volcano puzzle scored on eight columns from the Smithsonian catalogue
Volcanodle gives you six guesses to name one of 1,188 volcanoes in the Smithsonian Institution's Global Volcanism Program catalogue. There is no photograph and no silhouette, so you work only from what the catalogue records.
How a round goes
Type any volcano name from the pool and the grid answers with eight scored columns: Country, Region, Type, Tectonic setting, Elevation, Last eruption, Rock type and Historically observed. A tick means you matched that column, a cross means you did not. The answer is held on the server and every guess is evaluated there, so nothing in the page tells you the name before you find it.
The opening guess is usually about geography. Region uses the Global Volcanism Program's own division of the world into volcanic regions, so landing on Sunda-Banda Volcanic Regions or Eastern Africa Volcanic Regions narrows the field far more than a country match does.
The two columns that give you a near miss
Elevation and Last eruption are the only ordinal columns, and they are scored differently from the rest. Elevation is a bracket: submarine, under 500 m, 500 to 1500, 1500 to 3000, 3000 to 5000, or above 5000. Last eruption is one of three eras, older Holocene, 20th century or 21st century. A volcano with no recorded elevation reads as unknown and, like an undated eruption, sits outside the scale.
If your guess lands in a bracket next to the answer's, the cell comes back as a near match rather than a plain miss. Guess a 3,000 m cone, see a near on elevation, and you know the answer sits in the bracket just below or just above yours: two brackets instead of six. Volcanoes with no dated last eruption read as unknown, sit outside the scale, and can only score a hit or a miss.
Where the data comes from
Names, locations, types, tectonic settings, elevations, eruption history and rock types all come from the Global Volcanism Program of the Smithsonian Institution (Venzke, E. (ed.), Volcanoes of the World, volcano.si.edu). The teaching card at the end of a round is a verbatim excerpt of that volcano's GVP Geological Summary, with a link back to its page in the database.
This is a facts-only use of the database. Volcanodle carries no GVP images at all. The Global Volcanism Program asks to be cited when its data are reused; the game's attribution page does that, and you should do the same if you carry these facts anywhere else.
What you come away with
Where the catalogue has them, the reveal adds two things the grid never shows: the largest recorded eruption on the Volcanic Explosivity Index, and how many Holocene eruptions are on record. On roughly a quarter of days it has neither. Bonus rounds then work over other volcanoes in the pool, asking which of two stands higher, which one is in a named country, which erupts a named rock type, which erupted more recently, and which had the bigger eruption by VEI.
Play it for a few weeks and the shape of the catalogue starts to show through the grid: most of the pool sits above a subduction zone, and stratovolcano is by far the commonest type.
Questions
Is it the same puzzle for everyone?
Yes. One volcano a day, the same one for every player, rolling over at midnight UTC. The frozen calendar runs for 1,095 days.
Do I need an account?
No. There is no sign-up and no server-side profile. Your streak and your stats live in your browser's local storage, so clearing site data for the domain clears them.
Do I need to know summit heights in metres?
No. Elevation is only ever scored as a bracket, and the grid prints the bracket for each guess you make. The exact summit height is never shown at all, so it is not a number you have to hit.