diff --git a/backend/src/controllers/classes.ts b/backend/src/controllers/classes.ts
index 7526f7c4..40683c6a 100644
--- a/backend/src/controllers/classes.ts
+++ b/backend/src/controllers/classes.ts
@@ -1,6 +1,7 @@
 import { Request, Response } from 'express';
 import { createClass, getAllClasses, getClass, getClassStudents, getClassStudentsIds, getClassTeacherInvitations } from '../services/classes.js';
-import { ClassDTO } from '../interfaces/class.js';
+
+import { ClassDTO } from 'dwengo-1-common/src/interfaces/class';
 
 export async function getAllClassesHandler(req: Request, res: Response): Promise<void> {
     const full = req.query.full === 'true';
diff --git a/backend/src/interfaces/class.ts b/backend/src/interfaces/class.ts
index ea1d4901..c711b94b 100644
--- a/backend/src/interfaces/class.ts
+++ b/backend/src/interfaces/class.ts
@@ -2,14 +2,7 @@ import { Collection } from '@mikro-orm/core';
 import { Class } from '../entities/classes/class.entity.js';
 import { Student } from '../entities/users/student.entity.js';
 import { Teacher } from '../entities/users/teacher.entity.js';
-
-export interface ClassDTO {
-    id: string;
-    displayName: string;
-    teachers: string[];
-    students: string[];
-    joinRequests: string[];
-}
+import { ClassDTO } from 'dwengo-1-common/src/interfaces/class';
 
 export function mapToClassDTO(cls: Class): ClassDTO {
     return {
diff --git a/backend/src/interfaces/teacher-invitation.ts b/backend/src/interfaces/teacher-invitation.ts
index cddef566..a28aed5c 100644
--- a/backend/src/interfaces/teacher-invitation.ts
+++ b/backend/src/interfaces/teacher-invitation.ts
@@ -1,6 +1,7 @@
 import { TeacherInvitation } from '../entities/classes/teacher-invitation.entity.js';
-import { ClassDTO, mapToClassDTO } from './class.js';
+import { mapToClassDTO } from './class.js';
 import { mapToUserDTO, UserDTO } from './user.js';
+import { ClassDTO } from 'dwengo-1-common/src/interfaces/class';
 
 export interface TeacherInvitationDTO {
     sender: string | UserDTO;
diff --git a/backend/src/services/classes.ts b/backend/src/services/classes.ts
index 5b1e3cfc..542f8f19 100644
--- a/backend/src/services/classes.ts
+++ b/backend/src/services/classes.ts
@@ -1,8 +1,9 @@
 import { getClassRepository, getStudentRepository, getTeacherInvitationRepository, getTeacherRepository } from '../data/repositories.js';
-import { ClassDTO, mapToClassDTO } from '../interfaces/class.js';
+import { mapToClassDTO } from '../interfaces/class.js';
 import { mapToStudentDTO, StudentDTO } from '../interfaces/student.js';
 import { mapToTeacherInvitationDTO, mapToTeacherInvitationDTOIds, TeacherInvitationDTO } from '../interfaces/teacher-invitation.js';
 import { getLogger } from '../logging/initalize.js';
+import { ClassDTO } from 'dwengo-1-common/src/interfaces/class';
 
 const logger = getLogger();
 
diff --git a/backend/src/services/students.ts b/backend/src/services/students.ts
index 5382a67c..931162ff 100644
--- a/backend/src/services/students.ts
+++ b/backend/src/services/students.ts
@@ -1,10 +1,11 @@
 import { getClassRepository, getGroupRepository, getStudentRepository, getSubmissionRepository } from '../data/repositories.js';
-import { ClassDTO, mapToClassDTO } from '../interfaces/class.js';
+import { mapToClassDTO } from '../interfaces/class.js';
 import { GroupDTO, mapToGroupDTO, mapToGroupDTOId } from '../interfaces/group.js';
 import { mapToStudent, mapToStudentDTO, StudentDTO } from '../interfaces/student.js';
 import { mapToSubmissionDTO, mapToSubmissionDTOId, SubmissionDTO, SubmissionDTOId } from '../interfaces/submission.js';
 import { getAllAssignments } from './assignments.js';
 import { AssignmentDTO } from 'dwengo-1-common/src/interfaces/assignment';
+import { ClassDTO } from 'dwengo-1-common/src/interfaces/class';
 
 export async function getAllStudents(full: boolean): Promise<StudentDTO[] | string[]> {
     const studentRepository = getStudentRepository();
diff --git a/backend/src/services/teachers.ts b/backend/src/services/teachers.ts
index fced2b61..eca54214 100644
--- a/backend/src/services/teachers.ts
+++ b/backend/src/services/teachers.ts
@@ -1,9 +1,10 @@
 import { getClassRepository, getLearningObjectRepository, getQuestionRepository, getTeacherRepository } from '../data/repositories.js';
-import { ClassDTO, mapToClassDTO } from '../interfaces/class.js';
+import { mapToClassDTO } from '../interfaces/class.js';
 import { getClassStudents } from './classes.js';
 import { StudentDTO } from '../interfaces/student.js';
 import { mapToQuestionDTO, mapToQuestionId, QuestionDTO, QuestionId } from '../interfaces/question.js';
 import { mapToTeacher, mapToTeacherDTO, TeacherDTO } from '../interfaces/teacher.js';
+import { ClassDTO } from 'dwengo-1-common/src/interfaces/class';
 
 export async function getAllTeachers(full: boolean): Promise<TeacherDTO[] | string[]> {
     const teacherRepository = getTeacherRepository();
diff --git a/common/src/interfaces/class.d.ts b/common/src/interfaces/class.d.ts
new file mode 100644
index 00000000..c35c2dfc
--- /dev/null
+++ b/common/src/interfaces/class.d.ts
@@ -0,0 +1,7 @@
+export interface ClassDTO {
+    id: string;
+    displayName: string;
+    teachers: string[];
+    students: string[];
+    joinRequests: string[];
+}