diff --git a/package.json b/package.json
index 5181b12f03..3fd0ae1237 100644
--- a/package.json
+++ b/package.json
@@ -135,6 +135,7 @@
     "riot-compiler": "3.1.1",
     "riotify": "2.0.0",
     "rndstr": "1.0.0",
+    "s-age": "1.1.0",
     "serve-favicon": "2.3.2",
     "shelljs": "0.7.6",
     "subdomain": "1.2.0",
diff --git a/src/web/app/desktop/tags/user-profile.tag b/src/web/app/desktop/tags/user-profile.tag
index 12101ed633..710da14028 100644
--- a/src/web/app/desktop/tags/user-profile.tag
+++ b/src/web/app/desktop/tags/user-profile.tag
@@ -5,7 +5,7 @@
 	</div>
 	<div class="bio" if={ user.bio != '' }>{ user.bio }</div>
 	<div class="birthday" if={ user.birthday }>
-		<p><i class="fa fa-birthday-cake"></i>{ user.birthday.replace('-', '年').replace('-', '月') + '日' }</p>
+		<p><i class="fa fa-birthday-cake"></i>{ user.birthday.replace('-', '年').replace('-', '月') + '日' } ({ age(user.birthday) }歳)</p>
 	</div>
 	<div class="twitter" if={ user.twitter }>
 		<p><i class="fa fa-twitter"></i><a href={ 'https://twitter.com/' + user.twitter.screen_name } target="_blank">@{ user.twitter.screen_name }</a></p>
@@ -80,6 +80,8 @@
 
 	</style>
 	<script>
+		@age = require \s-age
+
 		@mixin \i
 
 		@user = @opts.user
diff --git a/src/web/app/mobile/tags/user.tag b/src/web/app/mobile/tags/user.tag
index 76b694a464..80884be313 100644
--- a/src/web/app/mobile/tags/user.tag
+++ b/src/web/app/mobile/tags/user.tag
@@ -12,7 +12,7 @@
 				<div class="bio">{ user.bio }</div>
 				<div class="info">
 					<p class="location" if={ user.location }><i class="fa fa-map-marker"></i>{ user.location }</p>
-					<p class="birthday" if={ user.birthday }><i class="fa fa-birthday-cake"></i>{ user.birthday.replace('-', '年').replace('-', '月') + '日' }</p>
+					<p class="birthday" if={ user.birthday }><i class="fa fa-birthday-cake"></i>{ user.birthday.replace('-', '年').replace('-', '月') + '日' } ({ age(user.birthday) }歳)</p>
 				</div>
 				<div class="friends"><a href="{ user.username }/following"><b>{ user.following_count }</b><i>フォロー</i></a><a href="{ user.username }/followers"><b>{ user.followers_count }</b><i>フォロワー</i></a></div>
 			</div>
@@ -154,6 +154,8 @@
 
 	</style>
 	<script>
+		@age = require \s-age
+
 		@mixin \i
 		@mixin \api