diff --git a/README.md b/README.md
index abdc254..c3f5150 100644
--- a/README.md
+++ b/README.md
@@ -76,7 +76,7 @@ Additionally, you may also be try [redirecting otp reports to Logger](https://he
 ## Configuration
 
 Configuration can be set using 2nd element of the tuple of the `:formatter` option in `Logger` configuration.
-For example in `config.exs`:
+For example in `runtime.exs`:
 
 ```elixir
 config :logger, :default_handler,
diff --git a/lib/logger_json.ex b/lib/logger_json.ex
index 0364185..c5cc64e 100644
--- a/lib/logger_json.ex
+++ b/lib/logger_json.ex
@@ -52,7 +52,7 @@ defmodule LoggerJSON do
   Configuration can be set using `new/1` helper of the formatter module,
   or by setting the 2nd element of the `:formatter` option tuple in `Logger` configuration.
 
-  For example in `config.exs`:
+  For example in `runtime.exs`:
 
       config :logger, :default_handler,
         formatter: LoggerJSON.Formatters.GoogleCloud.new(metadata: :all, project_id: "logger-101")