diff --git a/README.md b/README.md
index 511ce0e..99afb93 100644
--- a/README.md
+++ b/README.md
@@ -1,12 +1,20 @@
 # konami-card-wasm
-e-amusement card
+Convert e-amusement card ID and NFC ID to each other.
 
 ## Requirement
 - go 1.14.2
+- node.js
 
 ## Build
 ```shell script
 npm install
 npm run build
 ```
-빌드가 완료 된 후 build 폴더를 모듈처럼 사용하시면 됩니다!
+
+## Usage
+```node
+import { KonamiCard } from 'konami-card';
+
+KonamiCard.encode(nfcId).then(result => console.info(result));
+KonamiCard.decode(cardId).then(result => console.info(result));
+```