diff --git a/_config.yml b/_config.yml
index e3bc6be..4feeee0 100644
--- a/_config.yml
+++ b/_config.yml
@@ -49,13 +49,13 @@ social:
     # - https://www.facebook.com/username
     # - https://www.linkedin.com/in/username
 
-google_site_verification: google_meta_tag_verification # change to your verification string
+google_site_verification:               # fill in to your verification string
 
 # ↑ --------------------------
 
 
 google_analytics:
-  id: ''              # fill in your Google Analytics ID
+  id:                 # fill in your Google Analytics ID
   # Google Analytics pageviews report settings
   pv:
     proxy_endpoint:   # fill in the Google Analytics superProxy endpoint of Google App Engine
diff --git a/_includes/head.html b/_includes/head.html
index 710d47d..eac902b 100644
--- a/_includes/head.html
+++ b/_includes/head.html
@@ -40,7 +40,8 @@
   <link rel="dns-prefetch" href="https://fonts.gstatic.com">
 
   <!-- GA -->
-  {% if jekyll.environment == 'production' %}
+  {% if jekyll.environment == 'production'
+      and site.google_analytics.id != empty and site.google_analytics.id %}
     <link rel="preconnect" href="https://www.google-analytics.com" crossorigin="use-credentials">
     <link rel="dns-prefetch" href="https://www.google-analytics.com">
 
diff --git a/_includes/js-selector.html b/_includes/js-selector.html
index 219fe96..2e73f60 100644
--- a/_includes/js-selector.html
+++ b/_includes/js-selector.html
@@ -61,7 +61,7 @@
   <script defer src="{{ '/app.js' | relative_url }}"></script>
 
   <!-- GA -->
-  {% if site.google_analytics.id %}
+  {% if site.google_analytics.id != empty and site.google_analytics.id %}
     {% include google-analytics.html %}
   {% endif %}
 
diff --git a/assets/js/data/swcache.js b/assets/js/data/swcache.js
index ec648a0..4017f74 100644
--- a/assets/js/data/swcache.js
+++ b/assets/js/data/swcache.js
@@ -43,7 +43,7 @@ const resource = [
 
 /* The request url with below domain will be cached */
 const allowedDomains = [
-  {% if site.google_analytics.id != '' %}
+  {% if site.google_analytics.id != empty and site.google_analytics.id %}
     'www.googletagmanager.com',
     'www.google-analytics.com',
   {% endif %}