World Preview: See Your Minecraft Seed Before You Spawn
If you have ever rolled a new world and crossed your fingers for mushroom islands, cherry groves, or a sensible village layout, you already know the pain of guessing. World Preview is a Minecraft mod that turns seed roulette into something you can actually plan. Instead of generating a full world blind, it samples what your seed would produce and shows you a preview map you can explore before you commit blocks, biomes, and structures to disk.
That makes it especially useful for survival players who care about routes, builders who want dramatic terrain, and server hosts who need a fair spawn for everyone. The mod focuses on clarity: biomes first, then optional layers like structures and height, and even experimental views at specific Y levels when you want to peek at cave biomes or layered generation.
What World Preview Actually Does
World Preview adds a new Preview tab to the Singleplayer menu. When you open it, the mod picks a random seed and begins generating a biome map for the overworld by default. Structures are not shown at first, and a heightmap is not generated until you ask for it. Those defaults keep the first load lighter and easier to read, but you can change everything in Settings using the button at the top-left of the Preview tab.
Turn on structure sampling when you want to scout villages, strongholds, and other world features that matter to your run. You can also toggle which structure types appear on the preview so the map stays readable. Enable height sampling when terrain elevation matters for bases, bridges, or elytra flight paths, and switch between the biome map and a colorized heightmap view. If you enable Y-layer intersection sampling, the preview can show the blocks on the current Y layer, with the layer one step below shown in a lighter color so you can compare stacked geology at a glance.
Since version 1.1.0, there is experimental support for opening the preview while you are already inside a single-player world, which is handy when you want to cross-check what the sampler thinks your seed should look like against what you are standing on.
Moving Around the Preview (and Why Scroll Feels “Wrong” at First)
Clicking and dragging on the map moves you along the X and Z axes. As you pan, the mod follows a predictable load sequence: it fills in biomes for the current Y level, then structures if they are enabled, then the height map if it is enabled, then adjacent Y layers if those are enabled. If something looks empty for a moment, it is usually still sampling the next slice of the world.
Scrolling does not zoom. Instead, scrolling travels along the Y axis, which is how you inspect cave biomes and vertical variation without generating a full world. If you want a wider or tighter view, open Settings and adjust zoom through the resolution controls that change the visual size of a chunk. That separation between scroll-as-height and settings-as-zoom trips people up at first, but it is intentional once you start hunting deep biomes.
Installation, Versions, and Loaders
World Preview ships as a JAR you place in your instance’s mods folder. Always match the JAR to your exact Minecraft version and to your mod loader, whether you use Fabric or Forge. If you are on Fabric, you also need the Fabric API in the same folder so the mod’s hooks behave correctly. When you are juggling several mods across profiles, it helps to keep loaders, APIs, and the game version aligned so biome and structure registries stay consistent with what the preview samples.
Many players also like streamlining installs: this mod can be dropped in smoothly through the foxygame.net launcher, a flexible modern Minecraft launcher that lets you pull mods straight from the menu without hunting scattered download pages. If you already maintain a curated mod list for 1.20.x, that kind of one-place workflow keeps World Preview alongside terrain packs and QoL tweaks without breaking your folder hygiene.
Compatibility, Limits, and Fair Expectations
Support is aimed at Minecraft 1.20.x. Older releases are not supported, and multiplayer preview is not supported, so treat this as a single-player planning tool. On the bright side, World Preview is built to cooperate with many content mods and has been tested with packs like Terralith and Biomes O’ Plenty, which means new biomes and structures can show up in the preview when their registrations line up with your instance.
The mod also offers persistent seed storage, highlighting for specific biomes, and a configuration surface that modpack authors can extend. New biomes and structures can be registered through the datapack mechanism, which matches how Minecraft already expects world content to be declared.
- Performance: previews can spike CPU usage because the mod tries to compute biomes, structures, and heightmaps quickly. You can cap core usage under Settings, in the General section, if your machine fans spin up.
- Blank Y-layer views: if the intersection view looks white or black, your starting Y layer may be at build height; scroll down along the Y axis until blocks appear.
- TerraFirmaCraft note: World Preview can run with TFC, but the Y intersections view may stay white at all levels because of how that mod’s chunk generator exposes base columns. That is a known limitation of the information available to the preview, not a verdict on TFC itself.
Conclusion
World Preview is a practical bridge between Minecraft seeds and decisions. It respects the game’s biome and structure mechanics, layers optional height and Y-slice detail when you need it, and keeps the controls focused on exploration rather than blind worldgen. Pair it with a clean 1.20.x mod stack, tune sampling to your CPU comfort, and you will spend less time regretting seeds and more time crafting the world you actually wanted.