diff --git a/extractor/src/main/java/dev/_00a/valence_extractor/ClassComparator.java b/extractor/src/main/java/dev/_00a/valence_extractor/ClassComparator.java
new file mode 100644
index 0000000..d15c0ba
--- /dev/null
+++ b/extractor/src/main/java/dev/_00a/valence_extractor/ClassComparator.java
@@ -0,0 +1,21 @@
+package dev._00a.valence_extractor;
+
+import java.util.Comparator;
+
+/**
+ * Compare Class objects by their simple names lexicographically.
+ */
+public class ClassComparator implements Comparator<Class<?>> {
+    public ClassComparator() {
+    }
+
+    @Override
+    public int compare(Class<?> c1, Class<?> c2) {
+        return c1.getSimpleName().compareTo(c2.getSimpleName());
+    }
+
+    @Override
+    public boolean equals(Object comp) {
+        return comp instanceof ClassComparator;
+    }
+}
diff --git a/extractor/src/main/java/dev/_00a/valence_extractor/extractors/Entities.java b/extractor/src/main/java/dev/_00a/valence_extractor/extractors/Entities.java
index 4793b19..90f521b 100644
--- a/extractor/src/main/java/dev/_00a/valence_extractor/extractors/Entities.java
+++ b/extractor/src/main/java/dev/_00a/valence_extractor/extractors/Entities.java
@@ -1,6 +1,7 @@
 package dev._00a.valence_extractor.extractors;
 
 import com.google.gson.*;
+import dev._00a.valence_extractor.ClassComparator;
 import dev._00a.valence_extractor.DummyPlayerEntity;
 import dev._00a.valence_extractor.DummyWorld;
 import dev._00a.valence_extractor.Main;
@@ -272,7 +273,7 @@ public class Entities implements Main.Extractor {
         final var dataTrackerField = Entity.class.getDeclaredField("dataTracker");
         dataTrackerField.setAccessible(true);
 
-        var entitiesJson = new JsonObject();
+        var entitiesMap = new TreeMap<Class<? extends Entity>, JsonElement>(new ClassComparator());
 
         for (var entry : entityClassToType.entrySet()) {
             var entityClass = entry.getKey();
@@ -285,7 +286,7 @@ public class Entities implements Main.Extractor {
             final var entityInstance = entityType.equals(EntityType.PLAYER) ? DummyPlayerEntity.INSTANCE : entityType.create(DummyWorld.INSTANCE);
             final var dataTracker = (DataTracker) dataTrackerField.get(entityInstance);
 
-            while (entitiesJson.get(entityClass.getSimpleName()) == null) {
+            while (entitiesMap.get(entityClass) == null) {
                 var entityJson = new JsonObject();
 
                 var parent = entityClass.getSuperclass();
@@ -331,7 +332,7 @@ public class Entities implements Main.Extractor {
                 }
                 entityJson.add("fields", fieldsJson);
 
-                entitiesJson.add(entityClass.getSimpleName(), entityJson);
+                entitiesMap.put(entityClass, entityJson);
 
                 if (!hasParent) {
                     break;
@@ -342,6 +343,11 @@ public class Entities implements Main.Extractor {
             }
         }
 
+        var entitiesJson = new JsonObject();
+        for (var entry : entitiesMap.entrySet()) {
+            entitiesJson.add(entry.getKey().getSimpleName(), entry.getValue());
+        }
+
         return entitiesJson;
     }