diff --git a/calculator.rb b/calculator.rb
new file mode 100644
index 0000000..0200c5c
--- /dev/null
+++ b/calculator.rb
@@ -0,0 +1,39 @@
+def operator_method(num1, num2, operator)
+  case operator
+    when "+", "add"
+      puts num1 + num2
+    when "-", "subtract"
+      puts num1 - num2
+    when "*", "multiply"
+      puts num1 * num2
+    when "/", "divide"
+      while num2 <= 0
+        puts "please enter a number greater than 0"
+        num2 = gets.chomp
+      end
+      puts num1 / num2
+  end
+end
+
+
+def valid_number_user()
+  puts "please enter a valid number"
+  num = gets.chomp
+
+  while num.to_i.to_s != num
+    puts "please enter a valid number"
+    num = gets.chomp
+  end
+
+return num.to_i
+end
+
+puts "Welcome to the Calculator program! Which operator would you like to use\n 1. add(+)\n 2. subtract(-)\n 3. multiply(*)\n 4. divide(/)"
+
+operator = gets.chomp
+
+num1 = valid_number_user()
+num2 = valid_number_user()
+
+operator_method(num1, num2, operator)
+