The Feelmore50, a survey conducted by research firm System1, tests more than 700 ads chosen because they have won awards or have had viral success, with 56,400 consumers, scoring them on six criteria: emotion, story arc, fluency, soundtrack, narrative and character.
The Belvita ad, "Good mornings", which sees a chipper member of the onboard train staff attempt to cheer up glum-looking passengers on Blue Monday, topped the chart with an "emotion into action" score of 88.77.
Mark Boyd, founding partner at Gravity Road, said: "The challenge with most work on the internet these days is it is just more "stuff"? It's great to see people engage with a brand film that was designed to do just that. It is designed for that moment and medium."
Belvita pipped "Zipper and bears", a short film from Japanese zipper manufacturer YKK, created by Adk Asatsu DK, which finished second on 86.55. The Toy Story-esque tale sees the bears on a girl’s jumper come to life and attempt to zip it up to keep her warm as she sleeps.
In third, with 85.90, was an ad for Pernod Ricard’s Irish whisky Jameson, "The Long lost barrel", created by US agency EVB, which tells the tale of a very special barrel of whisky, before an amusing pay-off.
After Gravity Road, the next highest UK agency in the ranking was Adam & Eve/DDB, which appeared at both 32 (for Skittles, "Romance", on 83.21) and 34 (for The AA, "Singing baby", on 83.07).
In between these two was The Corner London, which scored 83.17 for Toys ‘R’ Us, "Geoffrey the part time reindeer".
The UK top 10 also included the Christmas ads from the BBC, Heathrow, Marks & Spencer and Amazon – but there was no room for the latest from John Lewis, "Moz the Monster".