diff --git a/leetcode/20 - validparenthesis/valid-parenthesis.js b/leetcode/20 - validparenthesis/valid-parenthesis.js
new file mode 100644
index 0000000..ab0dcef
--- /dev/null
+++ b/leetcode/20 - validparenthesis/valid-parenthesis.js	
@@ -0,0 +1,15 @@
+const isValid = string => {
+  const pairs = {'(': ')', '[': ']', '{': '}'}
+  let stack = []
+
+  for (const char of string) {
+    const lastChar = stack[stack.length - 1]
+    
+    if (char === pairs[lastChar]) 
+        stack.pop()
+    else 
+        stack.push(char)
+  }
+
+  return stack.length === 0
+}
\ No newline at end of file