Enter either value to convert to the other
Unicode shall be as decimal (NNN...) or hex (xNNNN)
UTF8 shall be as hex only (NN NN NN)
 
The last line may display printable characters for the UTF-8 bytes.
The characters displayed depend on how the values from 0x80 to
0xFF map under your OS. If all display you can just copy & paste
them into any plain text editor.
UTF8 bytes: