+1(514) 937-9445 or Toll-free (Canada & US) +1 (888) 947-9445
Msafiri said:
CBP state the tool is not 100% - problem seems to be more land crossings or where an I-94 has been used multiple times!

Where this was stated? Actually the tool missed 2 of my entries.
 
I really like that tool, but according to their data I'm still in the US (since 2012) and I'm an 'overstayer' ;)
Thank God I still have the stamps on my passport to prove I left the US after my transit.