diff --git a/bungee/src/main/java/com/turikhay/mc/mapmodcompanion/bungee/WorldIdPacketHandler.java b/bungee/src/main/java/com/turikhay/mc/mapmodcompanion/bungee/WorldIdPacketHandler.java
index 43be38c..67439a6 100644
--- a/bungee/src/main/java/com/turikhay/mc/mapmodcompanion/bungee/WorldIdPacketHandler.java
+++ b/bungee/src/main/java/com/turikhay/mc/mapmodcompanion/bungee/WorldIdPacketHandler.java
@@ -20,6 +20,6 @@ public WorldId tryRead(byte[] data) {
 
     @Override
     public WorldId getId(Server server) {
-        return new WorldId(server.getInfo().getName());
+        return WorldId.textual(server.getInfo().getName());
     }
 }
diff --git a/common/src/main/java/com/turikhay/mc/mapmodcompanion/worldid/WorldId.java b/common/src/main/java/com/turikhay/mc/mapmodcompanion/worldid/WorldId.java
index ac458f9..54af78f 100644
--- a/common/src/main/java/com/turikhay/mc/mapmodcompanion/worldid/WorldId.java
+++ b/common/src/main/java/com/turikhay/mc/mapmodcompanion/worldid/WorldId.java
@@ -5,26 +5,27 @@
 import javax.annotation.Nullable;
 import java.io.*;
 import java.nio.charset.StandardCharsets;
+import java.util.Objects;
 
-public class WorldId implements IdMessagePacket<WorldId> {
+public /* sealed */ abstract class WorldId implements IdMessagePacket<WorldId> {
     private static final int MAGIC_MARKER = 42;
 
-    private final String id;
-
-    public WorldId(String id) {
-        this.id = id;
-    }
-
     @Override
     public WorldId combineWith(WorldId packet) {
-        return new WorldId(packet.id + '_' + id);
+        if (this instanceof Numeric || packet instanceof Numeric) {
+            // combining with numeric id always "pollutes" the result
+            return new WorldId.Numeric(
+                    Objects.hash(getNumericId(), packet.getNumericId())
+            );
+        }
+        return new WorldId.Textual(packet.getStringId() + '_' + getStringId());
     }
 
     @Override
     public void constructPacket(DataOutputStream out) throws IOException {
         out.writeByte(0);         // packetId
         out.writeByte(MAGIC_MARKER); // 42 (literally)
-        byte[] data = id.getBytes(StandardCharsets.UTF_8);
+        byte[] data = getStringId().getBytes(StandardCharsets.UTF_8);
         out.write(data.length);     // length
         out.write(data);            // UTF
     }
@@ -45,16 +46,86 @@ public static WorldId tryRead(byte[] data) {
             if (read < length) {
                 return null;
             }
-            return new WorldId(new String(buf, StandardCharsets.UTF_8));
+            String id = new String(buf, StandardCharsets.UTF_8);
+            Numeric possiblyNumeric = Numeric.tryNumeric(id);
+            if (possiblyNumeric != null) {
+                return possiblyNumeric;
+            }
+            return new Textual(id);
         } catch (IOException ignored) {
         }
         return null;
     }
 
-    @Override
-    public String toString() {
-        return "WorldId{" +
-                "id='" + id + '\'' +
-                '}';
+    public static WorldId textual(String id) {
+        return new Textual(id);
+    }
+
+    public static WorldId numeric(int id) {
+        return new Numeric(id);
+    }
+
+    protected abstract int getNumericId();
+    protected abstract String getStringId();
+
+    static class Numeric extends WorldId {
+        private final int id;
+
+        public Numeric(int id) {
+            this.id = id;
+        }
+
+        @Override
+        protected int getNumericId() {
+            return id;
+        }
+
+        @Override
+        protected String getStringId() {
+            return String.valueOf(id);
+        }
+
+        @Override
+        public String toString() {
+            return "WorldId.Numeric{" +
+                    "id=" + id +
+                    '}';
+        }
+
+        @Nullable
+        public static Numeric tryNumeric(String value) {
+            int numeric;
+            try {
+                numeric = Integer.parseInt(value);
+            } catch (NumberFormatException ignored) {
+                return null;
+            }
+            return new Numeric(numeric);
+        }
+    }
+
+    static class Textual extends WorldId {
+        private final String id;
+
+        public Textual(String id) {
+            this.id = id;
+        }
+
+        @Override
+        protected int getNumericId() {
+            return id.hashCode();
+        }
+
+        @Override
+        protected String getStringId() {
+            return id;
+        }
+
+        @Override
+        public String toString() {
+            return "WorldId.Textual{" +
+                    "id='" + id + '\'' +
+                    '}';
+        }
     }
 }
diff --git a/spigot/src/main/java/com/turikhay/mc/mapmodcompanion/spigot/CompanionSpigot.java b/spigot/src/main/java/com/turikhay/mc/mapmodcompanion/spigot/CompanionSpigot.java
index d810300..3622a93 100644
--- a/spigot/src/main/java/com/turikhay/mc/mapmodcompanion/spigot/CompanionSpigot.java
+++ b/spigot/src/main/java/com/turikhay/mc/mapmodcompanion/spigot/CompanionSpigot.java
@@ -15,6 +15,10 @@ public class CompanionSpigot extends JavaPlugin implements Listener {
             System.getProperty(CompanionSpigot.class.getPackage().getName() + ".defaultId", "false")
     );
 
+    public static final boolean USE_TEXTUAL_WORLD_ID = Boolean.parseBoolean(
+            System.getProperty(CompanionSpigot.class.getPackage().getName() + ".useTextualId", "false")
+    );
+
     List<Handler<?>> handlers = Arrays.asList(
             new XaerosHandler(this),
             new WorldIdHandler(this)
diff --git a/spigot/src/main/java/com/turikhay/mc/mapmodcompanion/spigot/WorldIdHandler.java b/spigot/src/main/java/com/turikhay/mc/mapmodcompanion/spigot/WorldIdHandler.java
index ebfa76f..ce2e944 100644
--- a/spigot/src/main/java/com/turikhay/mc/mapmodcompanion/spigot/WorldIdHandler.java
+++ b/spigot/src/main/java/com/turikhay/mc/mapmodcompanion/spigot/WorldIdHandler.java
@@ -9,6 +9,7 @@
 
 import java.util.Arrays;
 import java.util.Locale;
+import java.util.UUID;
 
 import static com.turikhay.mc.mapmodcompanion.worldid.WorldIdCompanion.WORLD_ID_CHANNEL_NAME;
 import static com.turikhay.mc.mapmodcompanion.worldid.WorldIdCompanion.WORLD_ID_PACKET_DELAY;
@@ -36,7 +37,12 @@ public void scheduleLevelIdPacket(Runnable r, EventSource source) {
 
     @Override
     public WorldId getId(World world) {
-        return new WorldId(world.getUID().toString());
+        UUID uuid = world.getUID();
+        if (CompanionSpigot.USE_TEXTUAL_WORLD_ID) {
+            return WorldId.textual(uuid.toString());
+        } else {
+            return WorldId.numeric(uuid.hashCode());
+        }
     }
 
     @Override