diff --git a/packages/contracts/contracts/Semaphore.sol b/packages/contracts/contracts/Semaphore.sol
index e25c638f1..bc1636372 100644
--- a/packages/contracts/contracts/Semaphore.sol
+++ b/packages/contracts/contracts/Semaphore.sol
@@ -27,6 +27,14 @@ contract Semaphore is ISemaphore, SemaphoreGroups {
         verifier = _verifier;
     }
 
+    /// @dev See {SemaphoreGroups-_createGroup}.
+    function createGroup() external override returns (uint256 groupId) {
+        groupId = groupCounter++;
+        _createGroup(groupId, msg.sender);
+
+        groups[groupId].merkleTreeDuration = 1 hours;
+    }
+
     /// @dev See {SemaphoreGroups-_createGroup}.
     function createGroup(address admin) external override returns (uint256 groupId) {
         groupId = groupCounter++;
diff --git a/packages/contracts/contracts/interfaces/ISemaphore.sol b/packages/contracts/contracts/interfaces/ISemaphore.sol
index 71edfe6ae..e2c425e13 100644
--- a/packages/contracts/contracts/interfaces/ISemaphore.sol
+++ b/packages/contracts/contracts/interfaces/ISemaphore.sol
@@ -55,6 +55,9 @@ interface ISemaphore {
         uint256[8] points
     );
 
+    /// @dev See {SemaphoreGroups-_createGroup}.
+    function createGroup() external returns (uint256);
+
     /// @dev See {SemaphoreGroups-_createGroup}.
     function createGroup(address admin) external returns (uint256);
 
diff --git a/packages/contracts/test/Semaphore.ts b/packages/contracts/test/Semaphore.ts
index 817fa103c..8d5607ef6 100644
--- a/packages/contracts/test/Semaphore.ts
+++ b/packages/contracts/test/Semaphore.ts
@@ -54,6 +54,17 @@ describe("Semaphore", () => {
                 .to.emit(semaphoreContract, "GroupAdminUpdated")
                 .withArgs(groupId, ZeroAddress, accountAddresses[0])
         })
+
+        it("Should create a group without any parameters", async () => {
+            const groupId = 2
+
+            const transaction = await semaphoreContract["createGroup()"]()
+
+            await expect(transaction).to.emit(semaphoreContract, "GroupCreated").withArgs(groupId)
+            await expect(transaction)
+                .to.emit(semaphoreContract, "GroupAdminUpdated")
+                .withArgs(groupId, ZeroAddress, accountAddresses[0])
+        })
     })
 
     describe("# updateGroupMerkleTreeDuration", () => {
@@ -132,7 +143,7 @@ describe("Semaphore", () => {
         })
 
         it("Should add new members to an existing group", async () => {
-            const groupId = 2
+            const groupId = 3
             const members = [BigInt(1), BigInt(2), BigInt(3)]
             const group = new Group()
 
@@ -161,7 +172,7 @@ describe("Semaphore", () => {
         })
 
         it("Should update a member from an existing group", async () => {
-            const groupId = 3
+            const groupId = 4
             const members = [BigInt(1), BigInt(2), BigInt(3)]
             const group = new Group()
 
@@ -195,7 +206,7 @@ describe("Semaphore", () => {
         })
 
         it("Should remove a member from an existing group", async () => {
-            const groupId = 4
+            const groupId = 5
             const members = [BigInt(1), BigInt(2), BigInt(3)]
             const group = new Group()
 
@@ -229,7 +240,7 @@ describe("Semaphore", () => {
     })
 
     describe("# verifyProof", () => {
-        const groupId = 5
+        const groupId = 6
         const message = 2
         const identity = new Identity("0")
 
@@ -301,7 +312,7 @@ describe("Semaphore", () => {
         })
 
         it("Should not verify a proof if the group has no members", async () => {
-            const groupId = 6
+            const groupId = 7
             await semaphoreContract["createGroup(address)"](accountAddresses[0])
 
             const transaction = semaphoreContract.verifyProof(groupId, proof)
@@ -313,7 +324,7 @@ describe("Semaphore", () => {
     describe("# validateProof", () => {
         const message = 2
         const identity = new Identity("0")
-        const groupOneMemberId = 6
+        const groupOneMemberId = 7
 
         const group = new Group()
         const groupOneMember = new Group()