diff --git a/app/src/main/java/io/heckel/ntfy/db/Repository.kt b/app/src/main/java/io/heckel/ntfy/db/Repository.kt
index 15f76db7..4601798f 100644
--- a/app/src/main/java/io/heckel/ntfy/db/Repository.kt
+++ b/app/src/main/java/io/heckel/ntfy/db/Repository.kt
@@ -11,6 +11,8 @@ import io.heckel.ntfy.util.Log
 import io.heckel.ntfy.util.validUrl
 import java.util.concurrent.ConcurrentHashMap
 import java.util.concurrent.atomic.AtomicLong
+import com.google.gson.Gson
+import com.google.gson.reflect.TypeToken
 
 class Repository(private val sharedPrefs: SharedPreferences, private val database: Database) {
     private val subscriptionDao = database.subscriptionDao()
@@ -481,6 +483,35 @@ class Repository(private val sharedPrefs: SharedPreferences, private val databas
         }
     }
 
+    fun getCustomHeaders(): Map<String, String> {
+        val json = sharedPrefs.getString(SHARED_PREFS_CUSTOM_HEADERS, null)
+        return if (json != null) {
+            try {
+                val type = object : TypeToken<Map<String, String>>() {}.type
+                Gson().fromJson(json, type) ?: emptyMap()
+            } catch (e: Exception) {
+                Log.w("Repository", "Failed to parse custom headers", e)
+                emptyMap()
+            }
+        } else {
+            emptyMap()
+        }
+    }
+
+    fun setCustomHeaders(headers: Map<String, String>) {
+        val json = if (headers.isEmpty()) {
+            null
+        } else {
+            Gson().toJson(headers)
+        }
+
+        if (json == null) {
+            sharedPrefs.edit().remove(SHARED_PREFS_CUSTOM_HEADERS).apply()
+        } else {
+            sharedPrefs.edit().putString(SHARED_PREFS_CUSTOM_HEADERS, json).apply()
+        }
+    }
+
     private fun getState(subscriptionId: Long): ConnectionState {
         return connectionStatesLiveData.value!!.getOrElse(subscriptionId) { ConnectionState.NOT_APPLICABLE }
     }
@@ -506,6 +537,7 @@ class Repository(private val sharedPrefs: SharedPreferences, private val databas
         const val SHARED_PREFS_UNIFIED_PUSH_BASE_URL = "UnifiedPushBaseURL" // Legacy key required for migration to DefaultBaseURL
         const val SHARED_PREFS_DEFAULT_BASE_URL = "DefaultBaseURL"
         const val SHARED_PREFS_LAST_TOPICS = "LastTopics"
+        const val SHARED_PREFS_CUSTOM_HEADERS = "CustomHeaders"
 
         private const val LAST_TOPICS_COUNT = 3
 
diff --git a/app/src/main/java/io/heckel/ntfy/msg/ApiService.kt b/app/src/main/java/io/heckel/ntfy/msg/ApiService.kt
index 54c48ea9..bbcabf80 100644
--- a/app/src/main/java/io/heckel/ntfy/msg/ApiService.kt
+++ b/app/src/main/java/io/heckel/ntfy/msg/ApiService.kt
@@ -1,8 +1,10 @@
 package io.heckel.ntfy.msg
 
+import android.content.Context
 import android.os.Build
 import io.heckel.ntfy.BuildConfig
 import io.heckel.ntfy.db.Notification
+import io.heckel.ntfy.db.Repository
 import io.heckel.ntfy.db.User
 import io.heckel.ntfy.util.*
 import okhttp3.*
@@ -13,21 +15,26 @@ import java.nio.charset.StandardCharsets.UTF_8
 import java.util.concurrent.TimeUnit
 import kotlin.random.Random
 
-class ApiService {
+class ApiService(private val context: Context) {
+    private val repository = Repository.getInstance(context)
+
     private val client = OkHttpClient.Builder()
         .callTimeout(15, TimeUnit.SECONDS) // Total timeout for entire request
         .connectTimeout(15, TimeUnit.SECONDS)
         .readTimeout(15, TimeUnit.SECONDS)
         .writeTimeout(15, TimeUnit.SECONDS)
+        .addInterceptor(CustomHeadersInterceptor(repository))
         .build()
     private val publishClient = OkHttpClient.Builder()
         .callTimeout(5, TimeUnit.MINUTES) // Total timeout for entire request
         .connectTimeout(15, TimeUnit.SECONDS)
         .readTimeout(15, TimeUnit.SECONDS)
         .writeTimeout(15, TimeUnit.SECONDS)
+        .addInterceptor(CustomHeadersInterceptor(repository))
         .build()
     private val subscriberClient = OkHttpClient.Builder()
         .readTimeout(77, TimeUnit.SECONDS) // Assuming that keepalive messages are more frequent than this
+        .addInterceptor(CustomHeadersInterceptor(repository))
         .build()
     private val parser = NotificationParser()
 
@@ -165,6 +172,29 @@ class ApiService {
         }
     }
 
+    /**
+     * Interceptor that adds custom headers to all HTTP requests
+     */
+    private class CustomHeadersInterceptor(private val repository: Repository) : Interceptor {
+        override fun intercept(chain: Interceptor.Chain): Response {
+            val originalRequest = chain.request()
+            val customHeaders = repository.getCustomHeaders()
+
+            // If no custom headers, proceed with original request
+            if (customHeaders.isEmpty()) {
+                return chain.proceed(originalRequest)
+            }
+
+            // Add custom headers to the request
+            val requestBuilder = originalRequest.newBuilder()
+            customHeaders.forEach { (name, value) ->
+                requestBuilder.addHeader(name, value)
+            }
+
+            return chain.proceed(requestBuilder.build())
+        }
+    }
+
     class UnauthorizedException(val user: User?) : Exception()
     class EntityTooLargeException : Exception()
 
@@ -188,4 +218,4 @@ class ApiService {
             return builder
         }
     }
-}
+}
\ No newline at end of file
diff --git a/app/src/main/java/io/heckel/ntfy/msg/BroadcastService.kt b/app/src/main/java/io/heckel/ntfy/msg/BroadcastService.kt
index fb7f6d47..9ccabad2 100644
--- a/app/src/main/java/io/heckel/ntfy/msg/BroadcastService.kt
+++ b/app/src/main/java/io/heckel/ntfy/msg/BroadcastService.kt
@@ -68,7 +68,7 @@ class BroadcastService(private val ctx: Context) {
         }
 
         private fun send(ctx: Context, intent: Intent) {
-            val api = ApiService()
+            val api = ApiService(ctx)
             val baseUrl = getStringExtra(intent, "base_url") ?: ctx.getString(R.string.app_base_url)
             val topic = getStringExtra(intent, "topic") ?: return
             val message = getStringExtra(intent, "message") ?: return
@@ -128,4 +128,4 @@ class BroadcastService(private val ctx: Context) {
         private const val MESSAGE_SEND_ACTION = "io.heckel.ntfy.SEND_MESSAGE"
         private const val USER_ACTION_ACTION = "io.heckel.ntfy.USER_ACTION"
     }
-}
+}
\ No newline at end of file
diff --git a/app/src/main/java/io/heckel/ntfy/msg/CustomHeadersFragment.kt b/app/src/main/java/io/heckel/ntfy/msg/CustomHeadersFragment.kt
new file mode 100644
index 00000000..3582d241
--- /dev/null
+++ b/app/src/main/java/io/heckel/ntfy/msg/CustomHeadersFragment.kt
@@ -0,0 +1,198 @@
+package io.heckel.ntfy.ui
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.widget.EditText
+import androidx.appcompat.app.AlertDialog
+import androidx.preference.Preference
+import androidx.preference.PreferenceFragmentCompat
+import com.google.android.material.textfield.TextInputEditText
+import io.heckel.ntfy.R
+import io.heckel.ntfy.db.Repository
+import io.heckel.ntfy.util.Log
+
+class CustomHeadersFragment : PreferenceFragmentCompat() {
+    private lateinit var repository: Repository
+
+    override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
+        setPreferencesFromResource(R.xml.custom_headers_preferences, rootKey)
+        repository = Repository.getInstance(requireContext())
+
+        setupAddHeaderPreference()
+        loadCustomHeaders()
+    }
+
+    private fun setupAddHeaderPreference() {
+        findPreference<Preference>("add_custom_header")?.setOnPreferenceClickListener {
+            showAddHeaderDialog()
+            true
+        }
+    }
+
+    private fun loadCustomHeaders() {
+        val customHeaders = repository.getCustomHeaders()
+        val preferenceScreen = preferenceScreen
+
+        // Remove existing header preferences (keep only the "Add Header" preference)
+        val preferencesToRemove = mutableListOf<Preference>()
+        for (i in 0 until preferenceScreen.preferenceCount) {
+            val preference = preferenceScreen.getPreference(i)
+            if (preference.key != "add_custom_header") {
+                preferencesToRemove.add(preference)
+            }
+        }
+        preferencesToRemove.forEach { preferenceScreen.removePreference(it) }
+
+        // Add preferences for each custom header
+        customHeaders.forEach { (name, value) ->
+            val headerPreference = Preference(requireContext()).apply {
+                key = "header_$name"
+                title = name
+                summary = redactHeaderValue(value) // Show redacted value
+                setOnPreferenceClickListener {
+                    showEditHeaderDialog(name, value)
+                    true
+                }
+            }
+            preferenceScreen.addPreference(headerPreference)
+        }
+    }
+
+    private fun showAddHeaderDialog() {
+        val dialogView = LayoutInflater.from(requireContext())
+            .inflate(R.layout.dialog_custom_header, null)
+
+        val headerNameEdit = dialogView.findViewById<TextInputEditText>(R.id.header_name)
+        val headerValueEdit = dialogView.findViewById<TextInputEditText>(R.id.header_value)
+
+        AlertDialog.Builder(requireContext())
+            .setTitle(R.string.custom_headers_add_title)
+            .setView(dialogView)
+            .setPositiveButton(R.string.custom_headers_add) { _, _ ->
+                val name = headerNameEdit.text.toString().trim()
+                val value = headerValueEdit.text.toString().trim()
+
+                if (validateHeaderName(name)) {
+                    addCustomHeader(name, value)
+                } else {
+                    showInvalidHeaderDialog()
+                }
+            }
+            .setNegativeButton(R.string.user_dialog_button_cancel, null)
+            .show()
+    }
+
+    private fun showEditHeaderDialog(originalName: String, originalValue: String) {
+        val dialogView = LayoutInflater.from(requireContext())
+            .inflate(R.layout.dialog_custom_header, null)
+
+        val headerNameEdit = dialogView.findViewById<TextInputEditText>(R.id.header_name)
+        val headerValueEdit = dialogView.findViewById<TextInputEditText>(R.id.header_value)
+
+        headerNameEdit.setText(originalName)
+        headerValueEdit.setText(originalValue)
+
+        AlertDialog.Builder(requireContext())
+            .setTitle(R.string.custom_headers_edit_title)
+            .setView(dialogView)
+            .setPositiveButton(R.string.custom_headers_save) { _, _ ->
+                val name = headerNameEdit.text.toString().trim()
+                val value = headerValueEdit.text.toString().trim()
+
+                if (validateHeaderName(name)) {
+                    updateCustomHeader(originalName, name, value)
+                } else {
+                    showInvalidHeaderDialog()
+                }
+            }
+            .setNeutralButton(R.string.custom_headers_delete) { _, _ ->
+                showDeleteHeaderDialog(originalName)
+            }
+            .setNegativeButton(R.string.user_dialog_button_cancel, null)
+            .show()
+    }
+
+    private fun showDeleteHeaderDialog(headerName: String) {
+        AlertDialog.Builder(requireContext())
+            .setTitle(R.string.custom_headers_delete_title)
+            .setMessage(getString(R.string.custom_headers_delete_message, headerName))
+            .setPositiveButton(R.string.custom_headers_delete) { _, _ ->
+                deleteCustomHeader(headerName)
+            }
+            .setNegativeButton(R.string.user_dialog_button_cancel, null)
+            .show()
+    }
+
+    private fun showInvalidHeaderDialog() {
+        AlertDialog.Builder(requireContext())
+            .setTitle(R.string.custom_headers_error_title)
+            .setMessage(R.string.custom_headers_invalid_name)
+            .setPositiveButton(android.R.string.ok, null)
+            .show()
+    }
+
+    private fun validateHeaderName(name: String): Boolean {
+        if (name.isEmpty()) return false
+
+        // HTTP header names should only contain ASCII letters, digits, and hyphens
+        // and must not start or end with hyphens
+        val regex = Regex("^[A-Za-z0-9][A-Za-z0-9\\-]*[A-Za-z0-9]$|^[A-Za-z0-9]$")
+        return regex.matches(name)
+    }
+
+    private fun addCustomHeader(name: String, value: String) {
+        try {
+            val currentHeaders = repository.getCustomHeaders().toMutableMap()
+            currentHeaders[name] = value
+            repository.setCustomHeaders(currentHeaders)
+            loadCustomHeaders() // Refresh the UI
+            Log.d(TAG, "Added custom header: $name")
+        } catch (e: Exception) {
+            Log.w(TAG, "Failed to add custom header", e)
+        }
+    }
+
+    private fun updateCustomHeader(originalName: String, newName: String, newValue: String) {
+        try {
+            val currentHeaders = repository.getCustomHeaders().toMutableMap()
+
+            // Remove the old header if name changed
+            if (originalName != newName) {
+                currentHeaders.remove(originalName)
+            }
+
+            // Add/update the header
+            currentHeaders[newName] = newValue
+
+            repository.setCustomHeaders(currentHeaders)
+            loadCustomHeaders() // Refresh the UI
+            Log.d(TAG, "Updated custom header: $originalName -> $newName")
+        } catch (e: Exception) {
+            Log.w(TAG, "Failed to update custom header", e)
+        }
+    }
+
+    private fun deleteCustomHeader(name: String) {
+        try {
+            val currentHeaders = repository.getCustomHeaders().toMutableMap()
+            currentHeaders.remove(name)
+            repository.setCustomHeaders(currentHeaders)
+            loadCustomHeaders() // Refresh the UI
+            Log.d(TAG, "Deleted custom header: $name")
+        } catch (e: Exception) {
+            Log.w(TAG, "Failed to delete custom header", e)
+        }
+    }
+
+    private fun redactHeaderValue(value: String): String {
+        return when {
+            value.isEmpty() -> "(empty)"
+            value.length <= 3 -> "•".repeat(value.length)
+            else -> "•".repeat(8) // Always show 8 dots for longer values
+        }
+    }
+
+    companion object {
+        private const val TAG = "CustomHeadersFragment"
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/io/heckel/ntfy/service/SubscriberService.kt b/app/src/main/java/io/heckel/ntfy/service/SubscriberService.kt
index 60fbb477..eedba576 100644
--- a/app/src/main/java/io/heckel/ntfy/service/SubscriberService.kt
+++ b/app/src/main/java/io/heckel/ntfy/service/SubscriberService.kt
@@ -64,7 +64,7 @@ class SubscriberService : Service() {
     private val repository by lazy { (application as Application).repository }
     private val dispatcher by lazy { NotificationDispatcher(this, repository) }
     private val connections = ConcurrentHashMap<ConnectionId, Connection>()
-    private val api = ApiService()
+    private val api by lazy { ApiService(this) }
     private var notificationManager: NotificationManager? = null
     private var serviceNotification: Notification? = null
     private val refreshMutex = Mutex() // Ensure refreshConnections() is only run one at a time
@@ -377,4 +377,4 @@ class SubscriberService : Service() {
             return ServiceState.valueOf(value!!)
         }
     }
-}
+}
\ No newline at end of file
diff --git a/app/src/main/java/io/heckel/ntfy/ui/AddFragment.kt b/app/src/main/java/io/heckel/ntfy/ui/AddFragment.kt
index 8e56bab9..944c9478 100644
--- a/app/src/main/java/io/heckel/ntfy/ui/AddFragment.kt
+++ b/app/src/main/java/io/heckel/ntfy/ui/AddFragment.kt
@@ -23,7 +23,7 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 
 class AddFragment : DialogFragment() {
-    private val api = ApiService()
+    private val api by lazy { ApiService(requireContext()) }
 
     private lateinit var repository: Repository
     private lateinit var subscribeListener: SubscribeListener
@@ -435,4 +435,4 @@ class AddFragment : DialogFragment() {
         const val TAG = "NtfyAddFragment"
         private val DISALLOWED_TOPICS = listOf("docs", "static", "file") // If updated, also update in server
     }
-}
+}
\ No newline at end of file
diff --git a/app/src/main/java/io/heckel/ntfy/ui/DetailActivity.kt b/app/src/main/java/io/heckel/ntfy/ui/DetailActivity.kt
index 851f43ac..bf27fcb9 100644
--- a/app/src/main/java/io/heckel/ntfy/ui/DetailActivity.kt
+++ b/app/src/main/java/io/heckel/ntfy/ui/DetailActivity.kt
@@ -46,7 +46,7 @@ class DetailActivity : AppCompatActivity(), ActionMode.Callback, NotificationFra
         DetailViewModelFactory((application as Application).repository)
     }
     private val repository by lazy { (application as Application).repository }
-    private val api = ApiService()
+    private val api by lazy { ApiService(this) }
     private val messenger = FirebaseMessenger()
     private var notifier: NotificationService? = null // Context-dependent
     private var appBaseUrl: String? = null // Context-dependent
diff --git a/app/src/main/java/io/heckel/ntfy/ui/MainActivity.kt b/app/src/main/java/io/heckel/ntfy/ui/MainActivity.kt
index 1c4b0f52..06e63baf 100644
--- a/app/src/main/java/io/heckel/ntfy/ui/MainActivity.kt
+++ b/app/src/main/java/io/heckel/ntfy/ui/MainActivity.kt
@@ -58,7 +58,7 @@ class MainActivity : AppCompatActivity(), ActionMode.Callback, AddFragment.Subsc
         SubscriptionsViewModelFactory((application as Application).repository)
     }
     private val repository by lazy { (application as Application).repository }
-    private val api = ApiService()
+    private val api by lazy { ApiService(this) }
     private val messenger = FirebaseMessenger()
 
     // UI elements
diff --git a/app/src/main/java/io/heckel/ntfy/ui/ShareActivity.kt b/app/src/main/java/io/heckel/ntfy/ui/ShareActivity.kt
index 984f6afe..dc219ed1 100644
--- a/app/src/main/java/io/heckel/ntfy/ui/ShareActivity.kt
+++ b/app/src/main/java/io/heckel/ntfy/ui/ShareActivity.kt
@@ -21,7 +21,7 @@ import kotlinx.coroutines.launch
 
 class ShareActivity : AppCompatActivity() {
     private val repository by lazy { (application as Application).repository }
-    private val api = ApiService()
+    private val api by lazy { ApiService(this) }
 
     // File to share
     private var fileUri: Uri? = null
diff --git a/app/src/main/java/io/heckel/ntfy/work/PollWorker.kt b/app/src/main/java/io/heckel/ntfy/work/PollWorker.kt
index 582d0714..cc5cb6e1 100644
--- a/app/src/main/java/io/heckel/ntfy/work/PollWorker.kt
+++ b/app/src/main/java/io/heckel/ntfy/work/PollWorker.kt
@@ -26,7 +26,7 @@ class PollWorker(ctx: Context, params: WorkerParameters) : CoroutineWorker(ctx,
             Log.d(TAG, "Polling for new notifications")
             val repository = Repository.getInstance(applicationContext)
             val dispatcher = NotificationDispatcher(applicationContext, repository)
-            val api = ApiService()
+            val api = ApiService(applicationContext) // FIXED: Pass context parameter
 
             val baseUrl = inputData.getString(INPUT_DATA_BASE_URL)
             val topic = inputData.getString(INPUT_DATA_TOPIC)
@@ -72,4 +72,4 @@ class PollWorker(ctx: Context, params: WorkerParameters) : CoroutineWorker(ctx,
         const val INPUT_DATA_BASE_URL = "baseUrl"
         const val INPUT_DATA_TOPIC = "topic"
     }
-}
+}
\ No newline at end of file
diff --git a/app/src/main/res/layout/dialog_custom_header.xml b/app/src/main/res/layout/dialog_custom_header.xml
new file mode 100644
index 00000000..92e06328
--- /dev/null
+++ b/app/src/main/res/layout/dialog_custom_header.xml
@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical"
+    android:padding="16dp">
+
+    <com.google.android.material.textfield.TextInputLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:hint="@string/custom_headers_name_hint">
+
+        <com.google.android.material.textfield.TextInputEditText
+            android:id="@+id/header_name"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:inputType="text"
+            android:singleLine="true" />
+
+    </com.google.android.material.textfield.TextInputLayout>
+
+    <com.google.android.material.textfield.TextInputLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="8dp"
+        android:hint="@string/custom_headers_value_hint">
+
+        <com.google.android.material.textfield.TextInputEditText
+            android:id="@+id/header_value"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:inputType="text"
+            android:singleLine="true" />
+
+    </com.google.android.material.textfield.TextInputLayout>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values-de/strings.xml b/app/src/main/res/values-de/strings.xml
index aceed750..177194c1 100644
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@@ -350,4 +350,20 @@
     <string name="settings_advanced_exact_alarms_title">Genaue Alarme</string>
     <string name="settings_advanced_exact_alarms_true">ntfy kann genaue Alarme planen. Um WebSockets im Hintergrund wieder zu verbinden, sind genaue Alarme erforderlich. Hier tippen, um die Berechtigung zu widerrufen.</string>
     <string name="settings_advanced_exact_alarms_false">ntfy kann keine genauen Alarme planen. Um WebSockets im Hintergrund wieder zu verbinden, sind genaue Alarme erforderlich. Tippe hier, um die Berechtigung zu erteilen.</string>
+    <string name="settings_advanced_custom_headers_key">BenutzerdefinierteHeader</string>
+    <string name="settings_advanced_custom_headers_title">Benutzerdefinierte Header</string>
+    <string name="settings_advanced_custom_headers_summary">Benutzerdefinierte HTTP-Header zu allen Anfragen hinzufügen</string>
+    <string name="custom_headers_add_header">Header hinzufügen</string>
+    <string name="custom_headers_add_summary">Neuen benutzerdefinierten HTTP-Header hinzufügen</string>
+    <string name="custom_headers_add_title">Neuen Header hinzufügen</string>
+    <string name="custom_headers_edit_title">Header bearbeiten</string>
+    <string name="custom_headers_delete_title">Header löschen</string>
+    <string name="custom_headers_delete_message">Sind Sie sicher, dass Sie den Header „%1$s“ löschen möchten?</string>
+    <string name="custom_headers_add">Hinzufügen</string>
+    <string name="custom_headers_save">Speichern</string>
+    <string name="custom_headers_delete">Löschen</string>
+    <string name="custom_headers_error_title">Ungültiger Header</string>
+    <string name="custom_headers_invalid_name">Ungültige Zeichen im Header-Namen</string>
+    <string name="custom_headers_name_hint">Header-Name (z. B. CF-Access-Client-Id)</string>
+    <string name="custom_headers_value_hint">Header-Wert</string>
 </resources>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 49f9082b..19d10943 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -356,6 +356,9 @@
     <string name="settings_advanced_exact_alarms_title">Exact alarms</string>
     <string name="settings_advanced_exact_alarms_true">ntfy can schedule exact alarms. Exact alarms are required to reconnect WebSockets in the background. Click to revoke the permission.</string>
     <string name="settings_advanced_exact_alarms_false">ntfy cannot schedule exact alarms. Exact alarms are required to reconnect WebSockets in the background. Click to grant the permission.</string>
+    <string name="settings_advanced_custom_headers_key">CustomHeaders</string>
+    <string name="settings_advanced_custom_headers_title">Custom Headers</string>
+    <string name="settings_advanced_custom_headers_summary">Add custom HTTP headers to all requests</string>
     <string name="settings_about_header">About</string>
     <string name="settings_about_version_title">Version</string>
     <string name="settings_about_version_format">ntfy %1$s (%2$s)</string>
@@ -400,4 +403,19 @@
     <string name="user_dialog_button_cancel">Cancel</string>
     <string name="user_dialog_button_delete">Delete user</string>
     <string name="user_dialog_button_save">Save</string>
+
+    <!-- Custom Headers dialog  -->
+    <string name="custom_headers_add_header">Add Header</string>
+    <string name="custom_headers_add_summary">Add a new custom HTTP header</string>
+    <string name="custom_headers_add_title">Add Custom Header</string>
+    <string name="custom_headers_edit_title">Edit Custom Header</string>
+    <string name="custom_headers_delete_title">Delete Header</string>
+    <string name="custom_headers_delete_message">Are you sure you want to delete the header "%1$s"?</string>
+    <string name="custom_headers_add">Add</string>
+    <string name="custom_headers_save">Save</string>
+    <string name="custom_headers_delete">Delete</string>
+    <string name="custom_headers_error_title">Invalid Header</string>
+    <string name="custom_headers_invalid_name">Header name contains invalid characters</string>
+    <string name="custom_headers_name_hint">Header name (e.g., CF-Access-Client-Id)</string>
+    <string name="custom_headers_value_hint">Header value</string>
 </resources>
diff --git a/app/src/main/res/xml/custom_headers_preferences.xml b/app/src/main/res/xml/custom_headers_preferences.xml
new file mode 100644
index 00000000..08f981ec
--- /dev/null
+++ b/app/src/main/res/xml/custom_headers_preferences.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<PreferenceScreen xmlns:app="http://schemas.android.com/apk/res-auto">
+    <Preference
+        app:key="add_custom_header"
+        app:title="@string/custom_headers_add_header"
+        app:summary="@string/custom_headers_add_summary" />
+</PreferenceScreen>
\ No newline at end of file
diff --git a/app/src/main/res/xml/main_preferences.xml b/app/src/main/res/xml/main_preferences.xml
index 0ad3cec1..9e766b6d 100644
--- a/app/src/main/res/xml/main_preferences.xml
+++ b/app/src/main/res/xml/main_preferences.xml
@@ -98,6 +98,11 @@
                 app:key="@string/settings_advanced_clear_logs_key"
                 app:title="@string/settings_advanced_clear_logs_title"
                 app:summary="@string/settings_advanced_clear_logs_summary"/>
+        <Preference
+                app:key="@string/settings_advanced_custom_headers_key"
+                app:title="@string/settings_advanced_custom_headers_title"
+                app:summary="@string/settings_advanced_custom_headers_summary"
+                app:fragment="io.heckel.ntfy.ui.CustomHeadersFragment" />
     </PreferenceCategory>
     <PreferenceCategory app:title="@string/settings_about_header">
         <Preference