Usefulnes or Usefulness: How To spell?
The word Usefulnes is misspelled against Usefulness, a noun meaning "The quality or state of being useful; utility; serviceableness; advantage."
Usefulness has double 'ss' in the end mispronounced as 's'Remember double 'SS' appears in the end of this word which should not be misspelled with single 'S'
Wrong Spelling:  usefulne-s  Correct Spelling:  usefulne-ss 
Check more misspelled words of Usefulness to spell it correct.