diff --git a/README.md b/README.md
index 13118a9..eac3ccd 100644
--- a/README.md
+++ b/README.md
@@ -43,7 +43,7 @@ $ source env/bin/activate
 Start an empty card_data.json:
 
 ```text
-(env) $ echo "{}" > card-data.json
+(env) $ echo "{}" > card_data.json
 ```
 
 Now you can run the script to test: