diff --git a/app/src/main/java/org/koitharu/kotatsu/sync/SyncModule.kt b/app/src/main/java/org/koitharu/kotatsu/sync/SyncModule.kt
index 05e45f8c8..78688cac0 100644
--- a/app/src/main/java/org/koitharu/kotatsu/sync/SyncModule.kt
+++ b/app/src/main/java/org/koitharu/kotatsu/sync/SyncModule.kt
@@ -3,10 +3,13 @@ package org.koitharu.kotatsu.sync
 import org.koin.android.ext.koin.androidContext
 import org.koin.androidx.viewmodel.dsl.viewModel
 import org.koin.dsl.module
+import org.koitharu.kotatsu.sync.data.SyncAuthApi
 import org.koitharu.kotatsu.sync.ui.SyncAuthViewModel
 
 val syncModule
 	get() = module {
 
-		viewModel { SyncAuthViewModel(androidContext(), get()) }
+		factory { SyncAuthApi(androidContext(), get()) }
+
+		viewModel { SyncAuthViewModel(get()) }
 	}
\ No newline at end of file
diff --git a/app/src/main/java/org/koitharu/kotatsu/sync/data/AccountAuthenticator.kt b/app/src/main/java/org/koitharu/kotatsu/sync/data/AccountAuthenticator.kt
new file mode 100644
index 000000000..38a2c8696
--- /dev/null
+++ b/app/src/main/java/org/koitharu/kotatsu/sync/data/AccountAuthenticator.kt
@@ -0,0 +1,38 @@
+package org.koitharu.kotatsu.sync.data
+
+import android.accounts.Account
+import android.accounts.AccountManager
+import android.content.Context
+import kotlinx.coroutines.runBlocking
+import okhttp3.Authenticator
+import okhttp3.Request
+import okhttp3.Response
+import okhttp3.Route
+import org.koitharu.kotatsu.R
+
+class AccountAuthenticator(
+	context: Context,
+	private val account: Account,
+	private val authApi: SyncAuthApi,
+) : Authenticator {
+
+	private val accountManager = AccountManager.get(context)
+	private val tokenType = context.getString(R.string.account_type_sync)
+
+	override fun authenticate(route: Route?, response: Response): Request? {
+		val newToken = tryRefreshToken() ?: return null
+		accountManager.setAuthToken(account, tokenType, newToken)
+		return response.request.newBuilder()
+			.header("Authorization", "Bearer $newToken")
+			.build()
+	}
+
+	private fun tryRefreshToken() = runCatching {
+		runBlocking {
+			authApi.authenticate(
+				account.name,
+				accountManager.getPassword(account),
+			)
+		}
+	}.getOrNull()
+}
\ No newline at end of file
diff --git a/app/src/main/java/org/koitharu/kotatsu/sync/data/SyncAuthApi.kt b/app/src/main/java/org/koitharu/kotatsu/sync/data/SyncAuthApi.kt
new file mode 100644
index 000000000..744670526
--- /dev/null
+++ b/app/src/main/java/org/koitharu/kotatsu/sync/data/SyncAuthApi.kt
@@ -0,0 +1,30 @@
+package org.koitharu.kotatsu.sync.data
+
+import android.content.Context
+import okhttp3.OkHttpClient
+import okhttp3.Request
+import org.json.JSONObject
+import org.koitharu.kotatsu.R
+import org.koitharu.kotatsu.parsers.util.await
+import org.koitharu.kotatsu.parsers.util.parseJson
+import org.koitharu.kotatsu.utils.ext.toRequestBody
+
+class SyncAuthApi(
+	context: Context,
+	private val okHttpClient: OkHttpClient,
+) {
+
+	private val baseUrl = context.getString(R.string.url_sync_server)
+
+	suspend fun authenticate(email: String, password: String): String {
+		val body = JSONObject(
+			mapOf("email" to email, "password" to password)
+		).toRequestBody()
+		val request = Request.Builder()
+			.url("$baseUrl/auth")
+			.post(body)
+			.build()
+		val response = okHttpClient.newCall(request).await().parseJson()
+		return response.getString("token")
+	}
+}
\ No newline at end of file
diff --git a/app/src/main/java/org/koitharu/kotatsu/sync/domain/SyncHelper.kt b/app/src/main/java/org/koitharu/kotatsu/sync/domain/SyncHelper.kt
index 2b78a3e9d..8bba4be33 100644
--- a/app/src/main/java/org/koitharu/kotatsu/sync/domain/SyncHelper.kt
+++ b/app/src/main/java/org/koitharu/kotatsu/sync/domain/SyncHelper.kt
@@ -18,7 +18,9 @@ import org.koitharu.kotatsu.core.db.MangaDatabase.Companion.TABLE_MANGA_TAGS
 import org.koitharu.kotatsu.core.db.MangaDatabase.Companion.TABLE_TAGS
 import org.koitharu.kotatsu.parsers.util.json.mapJSONTo
 import org.koitharu.kotatsu.parsers.util.parseJson
+import org.koitharu.kotatsu.sync.data.AccountAuthenticator
 import org.koitharu.kotatsu.sync.data.AccountInterceptor
+import org.koitharu.kotatsu.sync.data.SyncAuthApi
 import org.koitharu.kotatsu.utils.GZipInterceptor
 import org.koitharu.kotatsu.utils.ext.toContentValues
 import org.koitharu.kotatsu.utils.ext.toJson
@@ -40,6 +42,7 @@ class SyncHelper(
 ) {
 
 	private val httpClient = OkHttpClient.Builder()
+		.authenticator(AccountAuthenticator(context, account, SyncAuthApi(context, OkHttpClient())))
 		.addInterceptor(AccountInterceptor(context, account))
 		.addInterceptor(GZipInterceptor())
 		.build()
diff --git a/app/src/main/java/org/koitharu/kotatsu/sync/ui/SyncAuthViewModel.kt b/app/src/main/java/org/koitharu/kotatsu/sync/ui/SyncAuthViewModel.kt
index bfe0ec079..da6dfa32c 100644
--- a/app/src/main/java/org/koitharu/kotatsu/sync/ui/SyncAuthViewModel.kt
+++ b/app/src/main/java/org/koitharu/kotatsu/sync/ui/SyncAuthViewModel.kt
@@ -1,44 +1,22 @@
 package org.koitharu.kotatsu.sync.ui
 
-import android.content.Context
 import kotlinx.coroutines.Dispatchers
-import okhttp3.OkHttpClient
-import okhttp3.Request
-import org.json.JSONObject
-import org.koitharu.kotatsu.R
 import org.koitharu.kotatsu.base.ui.BaseViewModel
-import org.koitharu.kotatsu.parsers.util.await
-import org.koitharu.kotatsu.parsers.util.parseJson
+import org.koitharu.kotatsu.sync.data.SyncAuthApi
 import org.koitharu.kotatsu.sync.domain.SyncAuthResult
 import org.koitharu.kotatsu.utils.SingleLiveEvent
-import org.koitharu.kotatsu.utils.ext.toRequestBody
-import java.util.*
 
 class SyncAuthViewModel(
-	context: Context,
-	private val okHttpClient: OkHttpClient,
+	private val api: SyncAuthApi,
 ) : BaseViewModel() {
 
-	private val baseUrl = context.getString(R.string.url_sync_server)
 	val onTokenObtained = SingleLiveEvent<SyncAuthResult>()
 
 	fun obtainToken(email: String, password: String) {
 		launchLoadingJob(Dispatchers.Default) {
-			authenticate(email, password)
-			val token = UUID.randomUUID().toString()
+			val token = api.authenticate(email, password)
 			val result = SyncAuthResult(email, password, token)
 			onTokenObtained.postCall(result)
 		}
 	}
-
-	private suspend fun authenticate(email: String, password: String) {
-		val body = JSONObject(
-			mapOf("email" to email, "password" to password)
-		).toRequestBody()
-		val request = Request.Builder()
-			.url("$baseUrl/register")
-			.post(body)
-			.build()
-		val response = okHttpClient.newCall(request).await().parseJson()
-	}
 }
\ No newline at end of file