diff --git a/mix.exs b/mix.exs
index 3a927f9..4f858e8 100644
--- a/mix.exs
+++ b/mix.exs
@@ -26,7 +26,7 @@ defmodule PublicSuffix.Mixfile do
 
   defp deps do
     [
-      {:idna, ">= 1.2.0 and < 3.0.0"},
+      {:idna, "~> 5.0"},
       # ex_doc and earmark are necessary to publish docs to hexdocs.pm.
       {:ex_doc, ">= 0.0.0", only: :dev},
       {:earmark, ">= 0.0.0", only: :dev},
diff --git a/mix.lock b/mix.lock
index 3b994ef..c682364 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,3 +1,4 @@
 %{"earmark": {:hex, :earmark, "0.2.1", "ba6d26ceb16106d069b289df66751734802777a3cbb6787026dd800ffeb850f3", [:mix], []},
   "ex_doc": {:hex, :ex_doc, "0.11.5", "0dc51cb84f8312162a2313d6c71573a9afa332333d8a332bb12540861b9834db", [:mix], [{:earmark, "~> 0.1.17 or ~> 0.2", [hex: :earmark, optional: true]}]},
-  "idna": {:hex, :idna, "1.2.0", "ac62ee99da068f43c50dc69acf700e03a62a348360126260e87f2b54eced86b2", [:rebar3], []}}
+  "idna": {:hex, :idna, "5.0.2", "ac203208ada855d95dc591a764b6e87259cb0e2a364218f215ad662daa8cd6b4", [:rebar3], [{:unicode_util_compat, "0.2.0", [hex: :unicode_util_compat, optional: false]}]},
+  "unicode_util_compat": {:hex, :unicode_util_compat, "0.2.0", "dbbccf6781821b1c0701845eaf966c9b6d83d7c3bfc65ca2b78b88b8678bfa35", [:rebar3], []}}