diff --git a/Doxyfile b/Doxyfile
index 4315f8cca..81d4c0df4 100644
--- a/Doxyfile
+++ b/Doxyfile
@@ -857,7 +857,7 @@ ALPHABETICAL_INDEX     = YES
 # the COLS_IN_ALPHA_INDEX tag can be used to specify the number of columns
 # in which this list will be split (can be a number in the range [1..20])
 
-COLS_IN_ALPHA_INDEX    = 5
+COLS_IN_ALPHA_INDEX    = 3
 
 # In case all classes in a project start with a common prefix, all
 # classes will be put under the same header in the alphabetical index.