diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/internal/util/BiomeMath.java b/worldedit-core/src/main/java/com/sk89q/worldedit/internal/util/BiomeMath.java
index a8e4a9518..f5ff7f22e 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/internal/util/BiomeMath.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/internal/util/BiomeMath.java
@@ -41,9 +41,9 @@ private BiomeMath() {
      * @return the index into the standard MC biome array
      */
     public static int computeBiomeIndex(int x, int y, int z) {
-        int l = x & HORIZONTAL_BIT_MASK;
-        int m = MathHelper.clamp(y, 0, VERTICAL_BIT_MASK);
-        int n = z & HORIZONTAL_BIT_MASK;
+        int l = (x >> 2) & HORIZONTAL_BIT_MASK;
+        int m = MathHelper.clamp(y >> 2, 0, VERTICAL_BIT_MASK);
+        int n = (z >> 2) & HORIZONTAL_BIT_MASK;
         return m << HORIZONTAL_SECTION_COUNT + HORIZONTAL_SECTION_COUNT
             | n << HORIZONTAL_SECTION_COUNT
             | l;
diff --git a/worldedit-fabric/src/main/java/com/sk89q/worldedit/fabric/FabricWorld.java b/worldedit-fabric/src/main/java/com/sk89q/worldedit/fabric/FabricWorld.java
index e5dc9253e..9204d55ab 100644
--- a/worldedit-fabric/src/main/java/com/sk89q/worldedit/fabric/FabricWorld.java
+++ b/worldedit-fabric/src/main/java/com/sk89q/worldedit/fabric/FabricWorld.java
@@ -36,7 +36,6 @@
 import com.sk89q.worldedit.fabric.internal.NBTConverter;
 import com.sk89q.worldedit.internal.Constants;
 import com.sk89q.worldedit.internal.block.BlockStateIdAccess;
-import com.sk89q.worldedit.internal.util.BiomeMath;
 import com.sk89q.worldedit.math.BlockVector2;
 import com.sk89q.worldedit.math.BlockVector3;
 import com.sk89q.worldedit.math.Vector3;
@@ -74,6 +73,7 @@
 import net.minecraft.world.World;
 import net.minecraft.world.WorldSaveHandler;
 import net.minecraft.world.biome.DefaultBiomeFeatures;
+import net.minecraft.world.biome.source.BiomeArray;
 import net.minecraft.world.chunk.Chunk;
 import net.minecraft.world.chunk.ChunkManager;
 import net.minecraft.world.chunk.ChunkStatus;
@@ -204,7 +204,9 @@ public boolean clearContainerBlockContents(BlockVector3 position) {
     @Override
     public BiomeType getBiome(BlockVector2 position) {
         checkNotNull(position);
-        return FabricAdapter.adapt(getWorld().getBiome(new BlockPos(position.getBlockX(), 0, position.getBlockZ())));
+        Chunk chunk = getWorld().getChunk(position.getX() >> 4, position.getZ() >> 4);
+        BiomeArray biomeArray = checkNotNull(chunk.getBiomeArray());
+        return FabricAdapter.adapt(biomeArray.getBiomeForNoiseGen(position.getX() >> 2, 0, position.getZ() >> 2));
     }
 
     @Override
@@ -216,9 +218,9 @@ public boolean setBiome(BlockVector2 position, BiomeType biome) {
         if (chunk == null) {
             return false;
         }
-        MutableBiomeArray biomeArray = MutableBiomeArray.inject(chunk.getBiomeArray());
+        MutableBiomeArray biomeArray = MutableBiomeArray.inject(checkNotNull(chunk.getBiomeArray()));
         // Temporary, while biome setting is 2D only
-        for (int i = 0; i < BiomeMath.VERTICAL_BIT_MASK; i++) {
+        for (int i = 0; i <= getMaxY(); i++) {
             biomeArray.setBiome(position.getX(), i, position.getZ(), FabricAdapter.adapt(biome));
         }
         chunk.setShouldSave(true);
diff --git a/worldedit-forge/src/main/java/com/sk89q/worldedit/forge/ForgeWorld.java b/worldedit-forge/src/main/java/com/sk89q/worldedit/forge/ForgeWorld.java
index 63737c65b..dba0d45c5 100644
--- a/worldedit-forge/src/main/java/com/sk89q/worldedit/forge/ForgeWorld.java
+++ b/worldedit-forge/src/main/java/com/sk89q/worldedit/forge/ForgeWorld.java
@@ -203,7 +203,10 @@ public boolean clearContainerBlockContents(BlockVector3 position) {
     @Override
     public BiomeType getBiome(BlockVector2 position) {
         checkNotNull(position);
-        return ForgeAdapter.adapt(getWorld().getBiome(new BlockPos(position.getBlockX(), 0, position.getBlockZ())));
+
+        IChunk chunk = getWorld().getChunk(position.getBlockX() >> 4, position.getBlockZ() >> 4);
+        BiomeContainer biomes = checkNotNull(chunk.getBiomes());
+        return ForgeAdapter.adapt(biomes.getNoiseBiome(position.getX() >> 2, 0, position.getZ() >> 2));
     }
 
     @Override
@@ -217,7 +220,7 @@ public boolean setBiome(BlockVector2 position, BiomeType biome) {
             return false;
         }
         // Temporary, while biome setting is 2D only
-        for (int i = 0; i < BiomeMath.VERTICAL_BIT_MASK; i++) {
+        for (int i = 0; i <= getMaxY(); i++) {
             int idx = BiomeMath.computeBiomeIndex(position.getX(), i, position.getZ());
             container.biomes[idx] = ForgeAdapter.adapt(biome);
         }