diff --git a/articles/context_processors.py b/articles/context_processors.py
index ed55370..2332c2d 100644
--- a/articles/context_processors.py
+++ b/articles/context_processors.py
@@ -7,3 +7,7 @@ def pages(request):
 
 def drafts_count(request):
     return {"drafts_count": Article.with_pages.filter(status=Article.DRAFT).count()}
+
+
+def date_format(request):
+    return {"CUSTOM_ISO": "Y-m-d\TH:i:sO"}
diff --git a/articles/templates/articles/comment_snippet.html b/articles/templates/articles/comment_snippet.html
index 2ac2681..e608df6 100644
--- a/articles/templates/articles/comment_snippet.html
+++ b/articles/templates/articles/comment_snippet.html
@@ -5,7 +5,7 @@
             <p class="metadata">
                 <a class="permalink" title="Permalink" href="#{{ comment.id }}">🔗</a>
                 <span class="username">{{ comment.username }}</span> |
-                <time datetime="{{ comment.created_at|date:'c' }}">
+                <time datetime="{{ comment.created_at|date:CUSTOM_ISO }}">
                     {{ comment.created_at|date:"DATETIME_FORMAT" }}
                 </time>
                 {% include "articles/admin_link_snippet.html" with article=comment %}
diff --git a/articles/templates/articles/metadata_snippet.html b/articles/templates/articles/metadata_snippet.html
index f44fc7a..db8b1dd 100644
--- a/articles/templates/articles/metadata_snippet.html
+++ b/articles/templates/articles/metadata_snippet.html
@@ -1,9 +1,9 @@
 {% load i18n %}
 <p class="date">
     {% if article.published_at %}
-        <time datetime="{{ article.published_at|date:'c' }}">{{ article.published_at|date }}</time>
+        <time datetime="{{ article.published_at|date:CUSTOM_ISO }}">{{ article.published_at|date }}</time>
     {% else %}
-        <time datetime="{{ article.updated_at|date:'c' }}">{{ article.updated_at|date }}</time>
+        <time datetime="{{ article.updated_at|date:CUSTOM_ISO }}">{{ article.updated_at|date }}</time>
     {% endif %}
     {% include "articles/admin_link_snippet.html" %}
 </p>
diff --git a/blog/settings.py b/blog/settings.py
index ba6da5b..22bbc96 100644
--- a/blog/settings.py
+++ b/blog/settings.py
@@ -96,6 +96,7 @@ TEMPLATES = [
                 "django.contrib.messages.context_processors.messages",
                 "articles.context_processors.pages",
                 "articles.context_processors.drafts_count",
+                "articles.context_processors.date_format",
             ],
         },
     },