diff --git a/src/common/WiFiSettings/WiFiForm.js b/src/common/WiFiSettings/WiFiForm.js
index 6005d6b..63bfd47 100644
--- a/src/common/WiFiSettings/WiFiForm.js
+++ b/src/common/WiFiSettings/WiFiForm.js
@@ -105,6 +105,7 @@ function DeviceForm({
                         label="SSID"
                         value={formData.SSID}
                         error={formErrors.SSID || null}
+                        helpText={HELP_TEXTS.ssid}
                         required
                         onChange={setFormValue((value) => ({
                             devices: {
diff --git a/src/common/WiFiSettings/WiFiGuestForm.js b/src/common/WiFiSettings/WiFiGuestForm.js
index 93380cd..7ae88c0 100644
--- a/src/common/WiFiSettings/WiFiGuestForm.js
+++ b/src/common/WiFiSettings/WiFiGuestForm.js
@@ -57,6 +57,7 @@ export default function WifiGuestForm({
                         label="SSID"
                         value={formData.SSID}
                         error={formErrors.SSID}
+                        helpText={HELP_TEXTS.ssid}
                         onChange={setFormValue((value) => ({
                             devices: {
                                 [formData.id]: {
diff --git a/src/common/WiFiSettings/WiFiSettings.js b/src/common/WiFiSettings/WiFiSettings.js
index a16d8d7..be455af 100644
--- a/src/common/WiFiSettings/WiFiSettings.js
+++ b/src/common/WiFiSettings/WiFiSettings.js
@@ -63,6 +63,12 @@ function prepDataToSubmit(formData) {
     return formData;
 }
 
+export function byteCount(string) {
+    const buffer = Buffer.from(string, "utf-8");
+    const count = buffer.byteLength;
+    return count;
+}
+
 export function validator(formData) {
     const formErrors = formData.devices.map((device) => {
         if (!device.enabled) return {};
@@ -71,6 +77,8 @@ export function validator(formData) {
         if (device.SSID.length > 32)
             errors.SSID = _("SSID can't be longer than 32 symbols");
         if (device.SSID.length === 0) errors.SSID = _("SSID can't be empty");
+        if (byteCount(device.SSID) > 32)
+            errors.SSID = _("SSID can't be longer than 32 bytes");
 
         if (device.password.length < 8)
             errors.password = _("Password must contain at least 8 symbols");
@@ -82,6 +90,8 @@ export function validator(formData) {
             guest_wifi_errors.SSID = _("SSID can't be longer than 32 symbols");
         if (device.guest_wifi.SSID.length === 0)
             guest_wifi_errors.SSID = _("SSID can't be empty");
+        if (byteCount(device.guest_wifi.SSID) > 32)
+            guest_wifi_errors.SSID = _("SSID can't be longer than 32 bytes");
 
         if (device.guest_wifi.password.length < 8)
             guest_wifi_errors.password = _(
diff --git a/src/common/WiFiSettings/__tests__/WiFiSettings.test.js b/src/common/WiFiSettings/__tests__/WiFiSettings.test.js
index 4923c67..7f533c2 100644
--- a/src/common/WiFiSettings/__tests__/WiFiSettings.test.js
+++ b/src/common/WiFiSettings/__tests__/WiFiSettings.test.js
@@ -19,7 +19,7 @@ import {
     twoDevices,
     threeDevices,
 } from "./__fixtures__/wifiSettings";
-import { WiFiSettings, validator } from "../WiFiSettings";
+import { WiFiSettings, validator, byteCount } from "../WiFiSettings";
 
 describe("<WiFiSettings/>", () => {
     let firstRender;
@@ -213,4 +213,8 @@ describe("<WiFiSettings/>", () => {
         ];
         expect(validator(threeDevices)).toEqual(threeDevicesFormErrors);
     });
+
+    it("ByteCount function", () => {
+        expect(byteCount("abc")).toEqual(3);
+    });
 });
diff --git a/src/common/WiFiSettings/__tests__/__snapshots__/WiFiSettings.test.js.snap b/src/common/WiFiSettings/__tests__/__snapshots__/WiFiSettings.test.js.snap
index 9d45f10..8a24692 100644
--- a/src/common/WiFiSettings/__tests__/__snapshots__/WiFiSettings.test.js.snap
+++ b/src/common/WiFiSettings/__tests__/__snapshots__/WiFiSettings.test.js.snap
@@ -5,7 +5,7 @@ exports[`<WiFiSettings/> Snapshot 2.4 GHz 1`] = `
 - First value
 + Second value
 
-@@ -245,207 +245,95 @@
+@@ -250,207 +250,95 @@
               value=\\"0\\"
             >
               auto
@@ -336,7 +336,7 @@ exports[`<WiFiSettings/> Snapshot guest network. 1`] = `
 - First value
 + Second value
 
-@@ -474,10 +474,89 @@
+@@ -479,10 +479,94 @@
           Parameters of the guest network can be set in the Guest network tab.
           
             </small>
@@ -375,6 +375,11 @@ exports[`<WiFiSettings/> Snapshot guest network. 1`] = `
 +             </button>
 +           </div>
 +         </div>
++         <small
++           class=\\"form-text text-muted\\"
++         >
++           SSID which contains non-standard characters could cause problems on some devices.
++         </small>
 +       </div>
 +       <div
 +         class=\\"form-group\\"
@@ -426,7 +431,7 @@ exports[`<WiFiSettings/> Snapshot guest network. 1`] = `
           class=\\"form-group switch\\"
         >
           <div
-@@ -501,10 +580,11 @@
+@@ -506,10 +590,11 @@
         <div
           class=\\"text-right\\"
         >
@@ -445,7 +450,7 @@ exports[`<WiFiSettings/> Snapshot one module enabled. 1`] = `
 - First value
 + Second value
 
-@@ -22,10 +22,462 @@
+@@ -22,10 +22,467 @@
                 Wi-Fi 1
               </h2>
             </label>
@@ -485,6 +490,11 @@ exports[`<WiFiSettings/> Snapshot one module enabled. 1`] = `
 +             </button>
 +           </div>
 +         </div>
++         <small
++           class=\\"form-text text-muted\\"
++         >
++           SSID which contains non-standard characters could cause problems on some devices.
++         </small>
 +       </div>
 +       <div
 +         class=\\"form-group\\"
diff --git a/src/common/WiFiSettings/constants.js b/src/common/WiFiSettings/constants.js
index 480c505..0018fef 100644
--- a/src/common/WiFiSettings/constants.js
+++ b/src/common/WiFiSettings/constants.js
@@ -19,6 +19,9 @@ export const HWMODES = {
     "11a": "5",
 };
 export const HELP_TEXTS = {
+    ssid: _(
+        `SSID which contains non-standard characters could cause problems on some devices.`
+    ),
     password: _(`
         WPA2 pre-shared key, that is required to connect to the network.
     `),