diff --git a/client/html/post_edit_sidebar.tpl b/client/html/post_edit_sidebar.tpl
index 4c055618..a66a375f 100644
--- a/client/html/post_edit_sidebar.tpl
+++ b/client/html/post_edit_sidebar.tpl
@@ -50,6 +50,11 @@
                     name: 'loop',
                     checked: ctx.post.flags.includes('loop'),
                 }) %>
+                <%= ctx.makeCheckbox({
+                    text: 'Sound',
+                    name: 'sound',
+                    checked: ctx.post.flags.includes('sound'),
+                }) %>
             </section>
         <% } %>
 
diff --git a/client/html/post_readonly_sidebar.tpl b/client/html/post_readonly_sidebar.tpl
index 54208ef0..401ce209 100644
--- a/client/html/post_readonly_sidebar.tpl
+++ b/client/html/post_readonly_sidebar.tpl
@@ -14,6 +14,9 @@
                 }[ctx.post.mimeType] %>
             </a>
             (<%- ctx.post.canvasWidth %>x<%- ctx.post.canvasHeight %>)
+            <% if (ctx.post.flags.includes('sound')) { %>
+                <i class='fa fa-volume-up'></i>
+            <% } %>
         </section>
 
         <section class='upload-info'>
diff --git a/client/js/controls/post_edit_sidebar_control.js b/client/js/controls/post_edit_sidebar_control.js
index dd8b66da..a5af449c 100644
--- a/client/js/controls/post_edit_sidebar_control.js
+++ b/client/js/controls/post_edit_sidebar_control.js
@@ -331,9 +331,7 @@ class PostEditSidebarControl extends events.EventTarget {
                         .value.toLowerCase() :
                     undefined,
 
-                flags: this._loopVideoInputNode ?
-                    (this._loopVideoInputNode.checked ? ['loop'] : []) :
-                    undefined,
+                flags: this._videoFlags,
 
                 tags: this._tagInputNode ?
                     misc.splitByWhitespace(this._tagInputNode.value) :
@@ -375,6 +373,18 @@ class PostEditSidebarControl extends events.EventTarget {
         return this._formNode.querySelector('.flags input[name=loop]');
     }
 
+    get _soundVideoInputNode() {
+        return this._formNode.querySelector('.flags input[name=sound]');
+    }
+
+    get _videoFlags() {
+        if (!this._loopVideoInputNode) return undefined;
+        let ret = [];
+        if (this._loopVideoInputNode.checked) ret.push('loop');
+        if (this._soundVideoInputNode.checked) ret.push('sound');
+        return ret;
+    }
+
     get _relationsInputNode() {
         return this._formNode.querySelector('.relations input');
     }
diff --git a/server/szurubooru/func/posts.py b/server/szurubooru/func/posts.py
index 9589a30f..4fcc087c 100644
--- a/server/szurubooru/func/posts.py
+++ b/server/szurubooru/func/posts.py
@@ -81,6 +81,7 @@ TYPE_MAP = {
 
 FLAG_MAP = {
     model.Post.FLAG_LOOP: 'loop',
+    model.Post.FLAG_SOUND: 'sound',
 }
 
 
diff --git a/server/szurubooru/model/post.py b/server/szurubooru/model/post.py
index f04ffb53..d682c1b0 100644
--- a/server/szurubooru/model/post.py
+++ b/server/szurubooru/model/post.py
@@ -154,6 +154,7 @@ class Post(Base):
     TYPE_FLASH = 'flash'
 
     FLAG_LOOP = 'loop'
+    FLAG_SOUND = 'sound'
 
     # basic meta
     post_id = sa.Column('id', sa.Integer, primary_key=True)