diff --git a/zack/id-to-path.pl b/zack/id-to-path.pl
new file mode 100755
index 0000000..e3bf51e
--- /dev/null
+++ b/zack/id-to-path.pl
@@ -0,0 +1,12 @@
+#!/usr/bin/perl
+use strict;
+while (my $l = <>) {
+    chomp $l;
+    $l = substr($l, -40);
+
+    print "/srv/softwareheritage/objects/";
+    print substr($l, 0, 2), "/";
+    print substr($l, 2, 2), "/";
+    print substr($l, 4, 2), "/";
+    print $l, "\n";
+}