diff --git a/Changes b/Changes
index 04b92a4d..374b7afc 100644
--- a/Changes
+++ b/Changes
@@ -1,6 +1,8 @@
 Revision history for {{$dist->name}}
 
 {{$NEXT}}
+  - float gets promoted to double when used as a varadic argument
+    (gh#323, gh#338)
 
 1.48_01   2021-06-22 00:32:02 -0600
   - Test forks in CI (gh#333, #334, #335)
diff --git a/lib/FFI/Platypus.pm b/lib/FFI/Platypus.pm
index 1e920693..959736b4 100644
--- a/lib/FFI/Platypus.pm
+++ b/lib/FFI/Platypus.pm
@@ -763,10 +763,18 @@ sub function
     $fixed_args = [];
   }
 
-  my $args = [@$fixed_args, @{ $var_args || [] } ];
   my $fixed_arg_count = defined $var_args ? scalar(@$fixed_args) : -1;
 
-  my @args = map { $self->{tp}->parse($_) || croak "unknown type: $_" } @$args;
+  my @args = map { $self->{tp}->parse($_) || croak "unknown type: $_" } @$fixed_args;
+  if($var_args)
+  {
+    push @args, map {
+      my $type = $self->{tp}->parse($_);
+      # https://github.com/PerlFFI/FFI-Platypus/issues/323
+      $type->type_code == 67 ? $self->{tp}->parse('double') : $type
+    } @$var_args;
+  }
+
   $ret = $self->{tp}->parse($ret) || croak "unknown type: $ret";
   my $address = $name =~ /^-?[0-9]+$/ ? $name : $self->find_symbol($name);
   croak "unable to find $name" unless defined $address || $self->ignore_not_found;
diff --git a/t/gh323.t b/t/gh323.t
new file mode 100644
index 00000000..b541bf56
--- /dev/null
+++ b/t/gh323.t
@@ -0,0 +1,38 @@
+use Test2::V0 -no_srand => 1;
+use FFI::Platypus;
+use FFI::Platypus::Memory qw( malloc free );
+
+foreach my $api (0,1,2)
+{
+
+  subtest "api => $api" => sub {
+
+    our $ffi = FFI::Platypus->new( api => $api, lib => [undef], experimental => ($api >=2 ? $api : undef));
+
+    $ffi->type('float' => 'my_float');
+
+    sub callit
+    {
+      my($type) = @_;
+
+      my $ptr = malloc 1024;
+      $ffi->function( sprintf => ['opaque','string'] => [$type] )->call($ptr, "%f", 3.14);
+      my $string = $ffi->cast('opaque' => 'string', $ptr);
+      free $ptr;
+      return $string;
+    }
+
+    my $double = callit('double');
+    my $float  = callit('float');
+    note "double = $double";
+    note "float  = $float";
+    is $float, $double;
+
+    $float  = callit('my_float');
+    note "my_float = $float";
+    is $float, $double;
+
+  };
+}
+
+done_testing;