Tryit Editor v1.8

Source Code:
<!DOCTYPE html> <html> <head> <script> function myFunction() { var x=document.getElementById("fname"); x.value=x.value.toUpperCase(); } </script> </head> <body> Enter your name: <input type="text" id="fname" onblur="myFunction()"> <p>When you leave the input field, a function is triggered which transforms the input text to upper case.</p> </body> </html>
Result:
W3Schools.com - Try it yourself