diff --git a/src/index.ts b/src/index.ts
index 40118ec..dc6fd69 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -2,6 +2,6 @@ import { codes } from './codes';
 import { CodeGetter } from './utils';
 import { ELocal, IFullCode } from './types';
 
-const errors = new CodeGetter(codes, ELocal.en_US);
+const errors = new CodeGetter(codes, ELocal.en);
 
 export { errors, ELocal, IFullCode };
diff --git a/src/resources/authentication/index.ts b/src/resources/authentication/index.ts
index a36791a..3567717 100644
--- a/src/resources/authentication/index.ts
+++ b/src/resources/authentication/index.ts
@@ -1,8 +1,10 @@
 import { II18n, IErrorRes, EHttpCode } from '../../types';
-import * as fr_FR from './locales/fr_FR.json';
-import * as en_US from './locales/en_US.json';
 
-const i18n: II18n = { fr_FR, en_US };
+// Locales
+import * as fr from './locales/fr.json';
+import * as en from './locales/en.json';
+
+const i18n: II18n = { fr, en };
 
 const authentication: IErrorRes = {
   client: {
diff --git a/src/resources/authentication/locales/en_US.json b/src/resources/authentication/locales/en.json
similarity index 100%
rename from src/resources/authentication/locales/en_US.json
rename to src/resources/authentication/locales/en.json
diff --git a/src/resources/authentication/locales/fr_FR.json b/src/resources/authentication/locales/fr.json
similarity index 100%
rename from src/resources/authentication/locales/fr_FR.json
rename to src/resources/authentication/locales/fr.json
diff --git a/src/resources/general/index.ts b/src/resources/general/index.ts
index 6f4dde2..e15dc70 100644
--- a/src/resources/general/index.ts
+++ b/src/resources/general/index.ts
@@ -1,10 +1,10 @@
 import { II18n, IErrorRes, EHttpCode } from '../../types';
 
-// Locals
-import * as fr_FR from './locales/fr_FR.json';
-import * as en_US from './locales/en_US.json';
+// Locales
+import * as fr from './locales/fr.json';
+import * as en from './locales/en.json';
 
-const i18n: II18n = { fr_FR, en_US };
+const i18n: II18n = { fr, en };
 
 const general: IErrorRes = {
   client: {},
diff --git a/src/resources/general/locales/en_US.json b/src/resources/general/locales/en.json
similarity index 100%
rename from src/resources/general/locales/en_US.json
rename to src/resources/general/locales/en.json
diff --git a/src/resources/general/locales/fr_FR.json b/src/resources/general/locales/fr.json
similarity index 100%
rename from src/resources/general/locales/fr_FR.json
rename to src/resources/general/locales/fr.json
diff --git a/src/resources/signIn/index.ts b/src/resources/signIn/index.ts
index 669d21a..a815be6 100644
--- a/src/resources/signIn/index.ts
+++ b/src/resources/signIn/index.ts
@@ -1,8 +1,10 @@
 import { II18n, IErrorRes, EHttpCode } from '../../types';
-import * as fr_FR from './locales/fr_FR.json';
-import * as en_US from './locales/en_US.json';
 
-const i18n: II18n = { fr_FR, en_US };
+// Locales
+import * as fr from './locales/fr.json';
+import * as en from './locales/en.json';
+
+const i18n: II18n = { fr, en };
 
 const authentication: IErrorRes = {
   client: {
diff --git a/src/resources/signIn/locales/en_US.json b/src/resources/signIn/locales/en.json
similarity index 100%
rename from src/resources/signIn/locales/en_US.json
rename to src/resources/signIn/locales/en.json
diff --git a/src/resources/signIn/locales/fr_FR.json b/src/resources/signIn/locales/fr.json
similarity index 100%
rename from src/resources/signIn/locales/fr_FR.json
rename to src/resources/signIn/locales/fr.json
diff --git a/src/types/index.ts b/src/types/index.ts
index db1c522..7f3f5e9 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -61,8 +61,8 @@ enum EHttpCode {
 }
 
 enum ELocal {
-  'fr_FR' = 'fr_FR',
-  'en_US' = 'en_US',
+  'fr' = 'fr',
+  'en' = 'en',
 }
 
 interface ICode {
diff --git a/tests/utils/codeGetter.ts b/tests/utils/codeGetter.ts
index 8b86cf5..0bdd9e6 100644
--- a/tests/utils/codeGetter.ts
+++ b/tests/utils/codeGetter.ts
@@ -17,12 +17,12 @@ describe('/src/utils/codeGetter.ts', () => {
       internal: {},
       external: {},
       i18n: {
-        en_US: {
+        en: {
           client: {
             testError2: 'testError2_en_US',
           },
         },
-        fr_FR: {
+        fr: {
           client: {
             testError2: 'testError2_fr_FR',
           },
@@ -32,7 +32,7 @@ describe('/src/utils/codeGetter.ts', () => {
   };
 
   beforeEach(() => {
-    errorsMock = new CodeGetter(fakeCodes, ELocal.fr_FR);
+    errorsMock = new CodeGetter(fakeCodes, ELocal.fr);
   });
 
   it('should get one error by key', () => {
@@ -50,24 +50,24 @@ describe('/src/utils/codeGetter.ts', () => {
   });
 
   it('should get translation of error with given lang', () => {
-    const err = errorsMock.get('carts:client:testError2').i18n(ELocal.en_US);
+    const err = errorsMock.get('carts:client:testError2').i18n(ELocal.en);
 
     expect(typeof err).toBe('string');
     expect(err).toBe('testError2_en_US');
   });
 
   it('should throw an error', () => {
-    let err: Error|null = null;
+    let err: Error | null = null;
 
     try {
-      errorsMock.get('carts:client:testError').i18n(ELocal.en_US);
+      errorsMock.get('carts:client:testError').i18n(ELocal.en);
     } catch (e) {
       err = e;
     }
 
     expect(err).toStrictEqual(
       Error(
-        'Translation for key carts:client:testError in en_US was not found',
+        'Translation for key carts:client:testError in en was not found',
       ),
     );
   });