diff --git a/src/fortuno/chartypes.f90 b/src/fortuno/chartypes.f90
index 43a655a..f1ae2fb 100644
--- a/src/fortuno/chartypes.f90
+++ b/src/fortuno/chartypes.f90
@@ -4,7 +4,7 @@
 
 !> Contains various types related to character representations.
 module fortuno_chartypes
-  use fortuno_utils, only : as_char, nl, string, to_upper
+  use fortuno_utils, only : as_char, as_upper, nl, string
   implicit none
 
   private
@@ -202,7 +202,7 @@ subroutine get_named_items_as_char_(items, repr, itemsep, namesep, capitalizenam
       associate(name => items(iitem)%name, val => valuestrings(iitem)%content)
         reprlen = len(name)
         repr(pos : pos + reprlen - 1) = name
-        if (capitalizename) repr(pos:pos) = to_upper(repr(pos:pos))
+        if (capitalizename) repr(pos:pos) = as_upper(repr(pos:pos))
         pos = pos + reprlen
         repr(pos : pos + nameseplen - 1) = namesep
         pos = pos + nameseplen
diff --git a/src/fortuno/utils.f90 b/src/fortuno/utils.f90
index 9c8bc7d..83f1f84 100644
--- a/src/fortuno/utils.f90
+++ b/src/fortuno/utils.f90
@@ -14,7 +14,7 @@ module fortuno_utils
   public :: nl
   public :: stderr, stdout
   public :: string, string_list
-  public :: to_upper
+  public :: as_upper
 
   !> New line character
   character(*), parameter :: nl = new_line("")
@@ -98,7 +98,7 @@ end function basename
 
 
   !> Converts a string to upper-case.
-  pure function to_upper(str) result(upperstr)
+  pure function as_upper(str) result(upperstr)
 
     !> String to convert
     character(*), intent(in) :: str
@@ -123,6 +123,6 @@ pure function to_upper(str) result(upperstr)
       end if
     end do
 
-  end function to_upper
+  end function as_upper
 
 end module fortuno_utils
\ No newline at end of file