diff --git a/_data/date_format.yml b/_data/date_format.yml
new file mode 100644
index 0000000..3040be7
--- /dev/null
+++ b/_data/date_format.yml
@@ -0,0 +1,9 @@
+#  The date format
+#  v2.1
+#  https://github.com/cotes2020/jekyll-theme-chirpy
+#  © 2020 Cotes Chung
+#  MIT Licensed
+
+
+tooltip: "%a, %b %e, %Y, %l:%M %p %z"
+post: "%b %e, %Y"
\ No newline at end of file
diff --git a/_includes/date-format.html b/_includes/date-format.html
deleted file mode 100644
index 2929063..0000000
--- a/_includes/date-format.html
+++ /dev/null
@@ -1,10 +0,0 @@
-<!--
- Define the liquid date formats.
- v2.0
- https://github.com/cotes2020/jekyll-theme-chirpy
- © 2019 Cotes Chung
- Published under the MIT License
--->
-
-{% assign TOOLTIP_DATE = "%a, %b %e, %Y, %l:%M %p %z" %}
-{% assign POST_DATE = "%b %e, %Y" %}
\ No newline at end of file
diff --git a/_includes/related-posts.html b/_includes/related-posts.html
index bb67ded..ae34eb9 100644
--- a/_includes/related-posts.html
+++ b/_includes/related-posts.html
@@ -53,7 +53,7 @@
         <a href="{{ post.url | relative_url }}">
           <div class="card-body">
             <span class="timeago small">
-                {{ post.date | date: POST_DATE }}
+                {{ post.date | date: site.data.date_format.post }}
                 <i class="unloaded">{{ post.date | date_to_xmlschema }}</i>
             </span>
             <h3 class="pt-0 mt-1 mb-3" data-toc-skip>{{ post.title }}</h3>
diff --git a/_layouts/category.html b/_layouts/category.html
index 5e9dd1f..1259311 100644
--- a/_layouts/category.html
+++ b/_layouts/category.html
@@ -6,8 +6,6 @@ layout: page
 # MIT Licensed
 ---
 
-{% include date-format.html %}
-
 <div id="page-category">
   <h1 class="pl-lg-2">
     <i class="far fa-folder-open fa-fw text-muted"></i>
@@ -20,7 +18,7 @@ layout: page
     <li class="d-flex justify-content-between pl-md-3 pr-md-3">
       <a href="{{ post.url | absolute_url }}">{{ post.title }}</a>
       <span class="dash flex-grow-1"></span>
-      <span class="text-muted small">{{ post.date | date: POST_DATE }}</span>
+      <span class="text-muted small">{{ post.date | date: site.data.date_format.post }}</span>
     </li>
     {% endfor %}
   </ul>
diff --git a/_layouts/home.html b/_layouts/home.html
index 6ebfe51..38d76e3 100644
--- a/_layouts/home.html
+++ b/_layouts/home.html
@@ -7,8 +7,6 @@ layout: page
 # MIT Licensed
 ---
 
-{% include date-format.html %}
-
 <div id="post-list">
   {% for post in paginator.posts %}
   <div class="post-preview">
@@ -24,8 +22,9 @@ layout: page
     <div class="post-meta text-muted pt-1">
       <!-- posted date -->
       <i class="far fa-clock fa-fw"></i>
-      <span class="timeago" data-toggle="tooltip" data-placement="bottom" title="{{ post.date | date: TOOLTIP_DATE }}">
-      {{ post.date | date: POST_DATE }}
+      <span class="timeago" data-toggle="tooltip" data-placement="bottom"
+        title="{{ post.date | date: site.data.date_format.tooltip }}">
+      {{ post.date | date: site.data.date_format.post }}
       <i class="unloaded">{{ post.date | date_to_xmlschema }}</i>
       </span>
       <!-- page views -->
diff --git a/_layouts/post.html b/_layouts/post.html
index c9382fc..45a1041 100644
--- a/_layouts/post.html
+++ b/_layouts/post.html
@@ -8,17 +8,19 @@ layout: default
 ---
 
 <div class="row">
-  {% include date-format.html %}
 
   <div id="post-wrapper" class="col-12 col-lg-11 col-xl-8">
+
     <div class="post pl-1 pr-1 pl-sm-2 pr-sm-2 pl-md-4 pr-md-4">
+
       <h1 data-toc-skip>{{ page.title }}</h1>
+
       <div class="post-meta text-muted d-flex flex-column">
         <!-- Published Date and Categoreis -->
         <div>
           <span class="timeago" data-toggle="tooltip" data-placement="bottom"
-           title="{{ page.date | date: TOOLTIP_DATE }}">
-            {{ page.date | date: POST_DATE }}
+           title="{{ page.date | date: site.data.date_format.tooltip }}">
+            {{ page.date | date: site.data.date_format.post }}
             <i class="unloaded">{{ page.date | date_to_xmlschema }}</i>
           </span>
           {% if page.categories.size > 0 %}on{% endif %}
@@ -61,8 +63,8 @@ layout: default
           Updated
           <span class="timeago lastmod"
             data-toggle="tooltip" data-placement="top"
-             title="{{ page.seo.date_modified | date: TOOLTIP_DATE }}">
-            {{ page.seo.date_modified | date: POST_DATE }}
+             title="{{ page.seo.date_modified | date: site.data.date_format.tooltip }}">
+            {{ page.seo.date_modified | date: site.data.date_format.post }}
             <i class="unloaded">{{ page.seo.date_modified | date_to_xmlschema}}</i>
           </span>
         </div>
diff --git a/_layouts/tag.html b/_layouts/tag.html
index b00d2c5..527f16f 100644
--- a/_layouts/tag.html
+++ b/_layouts/tag.html
@@ -7,8 +7,6 @@ layout: page
 # MIT Licensed
 ---
 
-{% include date-format.html %}
-
 <div id="page-tag">
   <h1 class="pl-lg-2">
     <i class="fa fa-tag fa-fw text-muted"></i>
@@ -20,7 +18,7 @@ layout: page
     <li class="d-flex justify-content-between pl-md-3 pr-md-3">
       <a href="{{ post.url | absolute_url }}">{{ post.title }}</a>
       <span class="dash flex-grow-1"></span>
-      <span class="text-muted small">{{ post.date | date: POST_DATE }}</span>
+      <span class="text-muted small">{{ post.date | date: site.data.date_format.post }}</span>
     </li>
     {% endfor %}
   </ul>