diff --git a/phpBB/styles/subSilver/template/bbcode.html b/phpBB/styles/subSilver/template/bbcode.html
index fe7ea4fa5d..908dce6a38 100644
--- a/phpBB/styles/subSilver/template/bbcode.html
+++ b/phpBB/styles/subSilver/template/bbcode.html
@@ -48,7 +48,7 @@
 
 <!-- BEGIN color --><span style="color: {COLOR}">{TEXT}</span><!-- END color -->
 
-<!-- BEGIN size --><span style="font-size: {SIZE}em; line-height: normal">{TEXT}</span><!-- END size -->
+<!-- BEGIN size --><span style="font-size: {SIZE}%; line-height: normal">{TEXT}</span><!-- END size -->
 
 <!-- BEGIN img --><img src="{URL}" alt="{L_IMAGE}" /><!-- END img -->