diff --git a/lib/authex.ex b/lib/authex.ex
index 99d4d80..5db9923 100644
--- a/lib/authex.ex
+++ b/lib/authex.ex
@@ -218,8 +218,9 @@ defmodule Authex do
 
   ## Options
     * `:time` - The base time (timestamp format) in which to use.
-    * `:ttl` - The time-to-live for the token in seconds. The lifetime is based
-      on the time provided via the options, or the current time if not provided.
+    * `:ttl` - The time-to-live for the token in seconds or `:infinity` if no expiration
+      is required. The lifetime is based on the time provided via the options,
+      or the current time if not provided.
 
   ## Example
 
diff --git a/lib/authex/token.ex b/lib/authex/token.ex
index b205e5a..9ddcfc9 100644
--- a/lib/authex/token.ex
+++ b/lib/authex/token.ex
@@ -39,7 +39,7 @@ defmodule Authex.Token do
   @type claims :: [claim]
   @type option ::
           {:time, integer}
-          | {:ttl, integer}
+          | {:ttl, integer | :infinity}
   @type options :: [option]
   @type compact :: binary
 
@@ -48,7 +48,7 @@ defmodule Authex.Token do
 
   ## Options
     * `:time` - the base time (timestamp format) in which to use.
-    * `:ttl` - the TTL for the token.
+    * `:ttl` - the TTL for the token or `:infinity` if no expiration is required.
 
   ## Examples
 
@@ -101,6 +101,10 @@ defmodule Authex.Token do
   end
 
   @doc false
+  def put_exp(token, _time, :infinity) do
+    %{token | exp: nil}
+  end
+
   def put_exp(token, time, ttl) do
     %{token | exp: time + ttl}
   end
diff --git a/mix.exs b/mix.exs
index 2419e0c..3046d01 100644
--- a/mix.exs
+++ b/mix.exs
@@ -1,7 +1,7 @@
 defmodule Authex.Mixfile do
   use Mix.Project
 
-  @version "2.0.0"
+  @version "2.1.0"
 
   def project do
     [
diff --git a/test/authex_test.exs b/test/authex_test.exs
index 4e1ffa9..12c752a 100644
--- a/test/authex_test.exs
+++ b/test/authex_test.exs
@@ -58,6 +58,11 @@ defmodule AuthexTest do
       assert %Token{exp: 20} = Authex.token(Auth, [], time: 0)
     end
 
+    test "can set an infinity exp through the ttl option" do
+      start_supervised(Auth, id: :one)
+      assert %Token{exp: nil} = Authex.token(Auth, [], ttl: :infinity)
+    end
+
     test "uses 3600 seconds as the default ttl" do
       start_supervised(Auth)
       assert %Token{exp: 3600} = Authex.token(Auth, [], time: 0)