The upcoming Borderlands 4 is the biggest series entry to date, and this applies to its open world as well. With the game set in the world of Kairos with a seamless sandbox world in tow, players will be able to explore its sizable world - but how big is it? Some fans may already have the answer to that question. As per Reddit user u/sherhazan, it might be comparable to The Elder Scrolls V: Skyrim.Bethesda's 2011 open-world action RPG is one of the most iconic sandbox games out there, so for a Borderlands sandbox world to be comparable would be interesting. Here are the details.Also Read: All returning characters confirmed in Borderlands 4 so farBorderlands 4's open world is allegedly 33 sq km, comparable to SkyrimVehicles will be key for navigating the open world in the upcoming sci-fi looter shooter (Image via 2K)Reddit user u/sherhazan deduced the world map size from the recent Borderlands 4 State of Play showcase, where the developers at Gearbox walked through the PS5 build of the game. To summarize, they determined the distance traveled between two points and, based on that scale, calculated an estimate for the playable portion of the map.While the full map, which is public information at this point, comes out at 54.4 sq km as per the output of a custom script written by the user, only taking in the playable land mass brings this number down to 32.64 sq km. This is quite comparable to The Elder Scrolls V: Skyrim, which is about 37 sq km in size.Also Read: Does Borderlands 4 have co-op and crossplay?BL4 Map Size — Area: 54,415,702 m² (54.4 km²) byu/sherhazan inBorderlands4While the number pales in comparison to other modern open-world titles like The Crew, Just Cause 3, and Xenoblade Chronicles X, it is still a big deal for the franchise. The series has traditionally featured mini-sandboxes cut off by loading screens.Borderlands 4, in comparison, goes a step further and features a seamless world with no waiting or cuts to load. Additionally, while 32 sq km will still be big for many players, the game features vehicles that will ease the burden of traversal, as the franchise has done in past entries.Regardless, we will have to wait and see for ourselves when Borderlands 4 launches on PC, PS5, and Xbox Series X|S on September 12, 2025. Note that the Nintendo Switch 2 version will arrive on October 3, 2025.Also Read: Borderlands 4 will finally include a solution for Claptrap's big problem