Names former Smiths guitarist Johnny Marr as his major inspiration. He started learning guitar playing after hearing Marr and was eventually able to play all Smiths songs by ear.
He is of Irish descent.
On 13 April 2014, Butler participated in the London Marathon to raise funds for children with cerebral palsy, described by Butler as one of the "worst starts in life".
I was obsessed with The Smiths and New Order. For a lot of people, it was seen as 'disco' against 'indie' - my inspiration came from both at the same time.
[2014; on participating in the London Marathon to raise funds for children with cerebral palsy] The problem is it's getting harder for families to get funding for therapy and children aren't getting the specialist support they need. So I'm raising money for the charity's treatment fund to make sure that children get seen as early as possible when it will have the greatest impact.