diff --git a/activejob/lib/active_job/queue_adapters/async_adapter.rb b/activejob/lib/active_job/queue_adapters/async_adapter.rb
index ebf6f384e3c8955dde4cad9df304ca3b63bbb983..53a7e3d53e571976aa672a09c3850bffa8502de8 100644
--- a/activejob/lib/active_job/queue_adapters/async_adapter.rb
+++ b/activejob/lib/active_job/queue_adapters/async_adapter.rb
@@ -31,7 +31,7 @@ module QueueAdapters
     # jobs. Since jobs share a single thread pool, long-running jobs will block
     # short-lived jobs. Fine for dev/test; bad for production.
     class AsyncAdapter
-      # See {Concurrent::ThreadPoolExecutor}[https://ruby-concurrency.github.io/concurrent-ruby/Concurrent/ThreadPoolExecutor.html] for executor options.
+      # See {Concurrent::ThreadPoolExecutor}[https://ruby-concurrency.github.io/concurrent-ruby/master/Concurrent/ThreadPoolExecutor.html] for executor options.
       def initialize(**executor_options)
         @scheduler = Scheduler.new(**executor_options)
       end