diff --git a/src/main/java/dan200/computercraft/core/apis/OSAPI.java b/src/main/java/dan200/computercraft/core/apis/OSAPI.java
index 7ec4b6878c..5975bb81be 100644
--- a/src/main/java/dan200/computercraft/core/apis/OSAPI.java
+++ b/src/main/java/dan200/computercraft/core/apis/OSAPI.java
@@ -303,7 +303,7 @@ public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull O
             {
                 // time
                 String param = optString( args, 0, "ingame" );
-                switch( param )
+                switch( param.toLowerCase( Locale.ENGLISH ) )
                 {
                     case "utc":
                     {
@@ -331,7 +331,7 @@ public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull O
             {
                 // day
                 String param = optString( args, 0, "ingame" );
-                switch( param )
+                switch( param.toLowerCase( Locale.ENGLISH ) )
                 {
                     case "utc":
                     {
@@ -385,7 +385,7 @@ public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull O
             {
                 // epoch
                 String param = optString( args, 0, "ingame" );
-                switch( param )
+                switch( param.toLowerCase( Locale.ENGLISH ) )
                 {
                     case "utc":
                     {