diff --git a/connection.js b/connection.js
index ffef33a..2e916b0 100644
--- a/connection.js
+++ b/connection.js
@@ -67,6 +67,11 @@ export async function createHsync(config) {
   hsyncClient.listeners = initListeners(hsyncClient);
   hsyncClient.relays = initRelays(hsyncClient);
 
+  // Enable auto-relay for web port (issue #15)
+  if (port) {
+    hsyncClient.relays.setWebPort(port);
+  }
+
   const events = new EventEmitter();
 
   hsyncClient.on = events.on.bind(events);
diff --git a/lib/socket-relays.js b/lib/socket-relays.js
index a41448a..de59d3f 100644
--- a/lib/socket-relays.js
+++ b/lib/socket-relays.js
@@ -14,6 +14,12 @@ export function setNet(netImpl) {
 
 export function initRelays(hsyncClient) {
   const cachedRelays = {};
+  let webPort = null;
+
+  function setWebPort(port) {
+    webPort = port;
+    debug('web port set for auto-relay:', port);
+  }
 
   function getSocketRelays() {
     const hKeys = Object.keys(cachedRelays);
@@ -45,8 +51,15 @@ export function initRelays(hsyncClient) {
       return `closeRelaySocket no matching socket for ${socketId}`;
     });
 
-    const relay = cachedRelays['p' + port];
+    let relay = cachedRelays['p' + port];
     debug('connect relay', port, socketId, peer.hostName);
+    
+    // Auto-create relay if port matches web port (issue #15)
+    if (!relay && webPort && port === webPort) {
+      debug('auto-creating relay for web port:', port);
+      relay = addSocketRelay({ port, targetHost: 'localhost', targetPort: port });
+    }
+    
     if (!relay) {
       throw new Error('no relay found for port: ' + port);
     }
@@ -112,11 +125,13 @@ export function initRelays(hsyncClient) {
   hsyncClient.addSocketRelay = addSocketRelay;
   hsyncClient.getSocketRelays = getSocketRelays;
   hsyncClient.connectSocket = connectSocket;
+  hsyncClient.setWebPort = setWebPort;
 
   return {
     // receiveListenerData,
     getSocketRelays,
     connectSocket,
     addSocketRelay,
+    setWebPort,
   };
 }
diff --git a/test/unit/socket-relays.test.js b/test/unit/socket-relays.test.js
index 6d10dd6..efd3223 100644
--- a/test/unit/socket-relays.test.js
+++ b/test/unit/socket-relays.test.js
@@ -68,6 +68,27 @@ describe('socket-relays', () => {
       expect(mockHsyncClient.addSocketRelay).toBeTypeOf('function');
       expect(mockHsyncClient.getSocketRelays).toBeTypeOf('function');
       expect(mockHsyncClient.connectSocket).toBeTypeOf('function');
+      expect(mockHsyncClient.setWebPort).toBeTypeOf('function');
+    });
+
+    it('should return setWebPort in returned object', () => {
+      const relays = initRelays(mockHsyncClient);
+
+      expect(relays.setWebPort).toBeTypeOf('function');
+    });
+  });
+
+  describe('setWebPort', () => {
+    let relays;
+
+    beforeEach(() => {
+      relays = initRelays(mockHsyncClient);
+    });
+
+    it('should store web port for auto-relay', () => {
+      // setWebPort stores the port internally - no return value
+      relays.setWebPort(3000);
+      // No error means success
     });
   });
 
@@ -201,6 +222,55 @@ describe('socket-relays', () => {
       ).toThrow('no relay found for port: 9999');
     });
 
+    it('should auto-create relay for web port (issue #15)', async () => {
+      // Set web port without explicit relay
+      relays.setWebPort(3000);
+
+      // Should NOT throw - should auto-create relay for web port
+      const result = await relays.connectSocket(mockPeer, {
+        port: 3000,
+        socketId: 'auto-relay-socket',
+        hostName: 'remote.example.com',
+      });
+
+      expect(result.socketId).toBe('auto-relay-socket');
+      expect(result.targetHost).toBe('localhost');
+      expect(result.targetPort).toBe(3000);
+      expect(mockSocket.connect).toHaveBeenCalledWith(3000, 'localhost', expect.any(Function));
+    });
+
+    it('should still throw for non-web ports when web port is set', () => {
+      relays.setWebPort(3000);
+
+      // Different port should still throw
+      expect(() =>
+        relays.connectSocket(mockPeer, {
+          port: 9999,
+          socketId: 'test-socket',
+          hostName: 'remote.example.com',
+        })
+      ).toThrow('no relay found for port: 9999');
+    });
+
+    it('should prefer explicit relay over auto-relay', async () => {
+      relays.setWebPort(3000);
+      relays.addSocketRelay({
+        port: 3000,
+        targetPort: 4000,
+        targetHost: 'custom-host.local',
+      });
+
+      const result = await relays.connectSocket(mockPeer, {
+        port: 3000,
+        socketId: 'explicit-relay-socket',
+        hostName: 'remote.example.com',
+      });
+
+      // Should use explicit relay config, not auto-relay
+      expect(result.targetHost).toBe('custom-host.local');
+      expect(result.targetPort).toBe(4000);
+    });
+
     it('should create socket and connect to relay target', async () => {
       relays.addSocketRelay({
         port: 3000,