diff --git a/packages/react-native-mmkv/cpp/HybridMMKV.cpp b/packages/react-native-mmkv/cpp/HybridMMKV.cpp
index 8ff2505d..e4b3dc31 100644
--- a/packages/react-native-mmkv/cpp/HybridMMKV.cpp
+++ b/packages/react-native-mmkv/cpp/HybridMMKV.cpp
@@ -55,6 +55,9 @@ HybridMMKV::HybridMMKV(const Configuration& config) : HybridObject(TAG) {
   }
 }
 
+std::string HybridMMKV::getId() {
+  return instance->mmapID();
+}
 double HybridMMKV::getSize() {
   return instance->actualSize();
 }
diff --git a/packages/react-native-mmkv/cpp/HybridMMKV.hpp b/packages/react-native-mmkv/cpp/HybridMMKV.hpp
index 946be28b..3454326c 100644
--- a/packages/react-native-mmkv/cpp/HybridMMKV.hpp
+++ b/packages/react-native-mmkv/cpp/HybridMMKV.hpp
@@ -19,6 +19,7 @@ class HybridMMKV final : public HybridMMKVSpec {
 
 public:
   // Properties
+  std::string getId() override;
   double getSize() override;
   bool getIsReadOnly() override;
 
diff --git a/packages/react-native-mmkv/nitrogen/generated/shared/c++/HybridMMKVSpec.cpp b/packages/react-native-mmkv/nitrogen/generated/shared/c++/HybridMMKVSpec.cpp
index abd7b66d..4b265680 100644
--- a/packages/react-native-mmkv/nitrogen/generated/shared/c++/HybridMMKVSpec.cpp
+++ b/packages/react-native-mmkv/nitrogen/generated/shared/c++/HybridMMKVSpec.cpp
@@ -14,6 +14,7 @@ namespace margelo::nitro::mmkv {
     HybridObject::loadHybridMethods();
     // load custom methods/properties
     registerHybrids(this, [](Prototype& prototype) {
+      prototype.registerHybridGetter("id", &HybridMMKVSpec::getId);
       prototype.registerHybridGetter("size", &HybridMMKVSpec::getSize);
       prototype.registerHybridGetter("isReadOnly", &HybridMMKVSpec::getIsReadOnly);
       prototype.registerHybridMethod("set", &HybridMMKVSpec::set);
diff --git a/packages/react-native-mmkv/nitrogen/generated/shared/c++/HybridMMKVSpec.hpp b/packages/react-native-mmkv/nitrogen/generated/shared/c++/HybridMMKVSpec.hpp
index 9952d908..a37e5943 100644
--- a/packages/react-native-mmkv/nitrogen/generated/shared/c++/HybridMMKVSpec.hpp
+++ b/packages/react-native-mmkv/nitrogen/generated/shared/c++/HybridMMKVSpec.hpp
@@ -51,6 +51,7 @@ namespace margelo::nitro::mmkv {
 
     public:
       // Properties
+      virtual std::string getId() = 0;
       virtual double getSize() = 0;
       virtual bool getIsReadOnly() = 0;
 
diff --git a/packages/react-native-mmkv/src/createMMKV/createMMKV.ts b/packages/react-native-mmkv/src/createMMKV/createMMKV.ts
index 8a77e953..83c8633c 100644
--- a/packages/react-native-mmkv/src/createMMKV/createMMKV.ts
+++ b/packages/react-native-mmkv/src/createMMKV/createMMKV.ts
@@ -13,7 +13,7 @@ let platformContext: MMKVPlatformContext | undefined
 export function createMMKV(configuration?: Configuration): MMKV {
   if (isTest()) {
     // In a test environment, we mock the MMKV instance.
-    return createMockMMKV()
+    return createMockMMKV(configuration)
   }
 
   if (platformContext == null) {
diff --git a/packages/react-native-mmkv/src/createMMKV/createMMKV.web.ts b/packages/react-native-mmkv/src/createMMKV/createMMKV.web.ts
index 790b543b..f99ae585 100644
--- a/packages/react-native-mmkv/src/createMMKV/createMMKV.web.ts
+++ b/packages/react-native-mmkv/src/createMMKV/createMMKV.web.ts
@@ -85,6 +85,9 @@ export function createMMKV(
   }
 
   return {
+    id: config.id,
+    size: 0,
+    isReadOnly: false,
     clearAll: () => {
       const keys = Object.keys(storage())
       for (const key of keys) {
@@ -130,8 +133,6 @@ export function createMMKV(
     recrypt: () => {
       throw new Error('`recrypt(..)` is not supported on Web!')
     },
-    size: 0,
-    isReadOnly: false,
     trim: () => {
       // no-op
     },
diff --git a/packages/react-native-mmkv/src/createMMKV/createMockMMKV.ts b/packages/react-native-mmkv/src/createMMKV/createMockMMKV.ts
index 66453961..02871993 100644
--- a/packages/react-native-mmkv/src/createMMKV/createMockMMKV.ts
+++ b/packages/react-native-mmkv/src/createMMKV/createMockMMKV.ts
@@ -1,9 +1,12 @@
 import type { MMKV } from '../specs/MMKV.nitro'
+import type { Configuration } from '../specs/MMKVFactory.nitro'
 
 /**
  * Mock MMKV instance when used in a Jest/Test environment.
  */
-export function createMockMMKV(): MMKV {
+export function createMockMMKV(
+  config: Configuration = { id: 'mmkv.default' }
+): MMKV {
   const storage = new Map<string, string | boolean | number | ArrayBuffer>()
   const listeners = new Set<(key: string) => void>()
 
@@ -14,6 +17,11 @@ export function createMockMMKV(): MMKV {
   }
 
   return {
+    id: config.id,
+    get size(): number {
+      return storage.size
+    },
+    isReadOnly: false,
     clearAll: () => {
       const keysBefore = storage.keys()
       storage.clear()
@@ -55,10 +63,6 @@ export function createMockMMKV(): MMKV {
     recrypt: () => {
       console.warn('Encryption is not supported in mocked MMKV instances!')
     },
-    get size(): number {
-      return storage.size
-    },
-    isReadOnly: false,
     trim: () => {
       // no-op
     },
diff --git a/packages/react-native-mmkv/src/specs/MMKV.nitro.ts b/packages/react-native-mmkv/src/specs/MMKV.nitro.ts
index 1c922e34..cb5b331e 100644
--- a/packages/react-native-mmkv/src/specs/MMKV.nitro.ts
+++ b/packages/react-native-mmkv/src/specs/MMKV.nitro.ts
@@ -5,6 +5,19 @@ export interface Listener {
 }
 
 export interface MMKV extends HybridObject<{ ios: 'c++'; android: 'c++' }> {
+  /**
+   * Get the ID of this {@linkcode MMKV} instance.
+   */
+  readonly id: string
+  /**
+   * Get the current total size of the storage, in bytes.
+   */
+  readonly size: number
+  /**
+   * Returns whether this instance is in read-only mode or not.
+   * If this is `true`, you can only use "get"-functions.
+   */
+  readonly isReadOnly: boolean
   /**
    * Set a {@linkcode value} for the given {@linkcode key}.
    *
@@ -75,15 +88,6 @@ export interface MMKV extends HybridObject<{ ios: 'c++'; android: 'c++' }> {
    * In most applications, this is not needed at all.
    */
   trim(): void
-  /**
-   * Get the current total size of the storage, in bytes.
-   */
-  readonly size: number
-  /**
-   * Returns whether this instance is in read-only mode or not.
-   * If this is `true`, you can only use "get"-functions.
-   */
-  readonly isReadOnly: boolean
   /**
    * Adds a value changed listener. The Listener will be called whenever any value
    * in this storage instance changes (set or delete).