diff --git a/Python/3.6.3/decrypt.py b/Python/3.6.3/decrypt.py
new file mode 100644
index 0000000..ec29e3b
--- /dev/null
+++ b/Python/3.6.3/decrypt.py
@@ -0,0 +1,11 @@
+def decrypt():
+  initial = input('Give the message to encrypt (CAPITALS - no space or special characters) : ')
+  key = input('Give the key (lowercase letters - no space or special characters) : ')
+  lkey = len(key)
+  numeros1 = [ord(i) for i in key]
+  numeros2 = [ord(i) for i in initial]
+  output = ''
+  for i in range(len(numeros2)):
+    value = (numeros2[i] - numeros1[i % lkey]) % 26
+    output += chr(value + 65)
+  print('The decrypted message is : ' + output)