Fall Out Boy's Pete Wentz has described the band's new album 'Mania' as a ''testament to our fanbase''.

The 38-year-old bassist was shocked when his band's seventh studio album topped the Billboard 200 charts the week after its release on January 19, and has said the success of the record shows how ''loyal'' their fans are.

He said: ''[It is a] testament to our fanbase. They've been very loyal. I don't think we're an easy, popular act to swallow. It's just because they go out and buy the record. There's no other ginormous campaign. I think it's just a testament to them more than anything.''

Although he is ''super excited'' the album is doing so well, the 'Hold Me Tight or Don't' hitmaker - who is joined by Patrick Stump, Joe Trohman, and Andy Hurley in the band - insists that ''numbers don't fill a void that you have. It just doesn't at all.''

However, scoring a number one album has ''vindicated'' the band's decision to delay releasing the record, after it was originally slated for release in September last year.

When asked by Billboard's 'Pop Shop Podcast' if it was a relief to have the album do well after pushing back its release, Pete said: ''I think it vindicated the idea of pushing back. I was really nervous about pushing it back. I feel like letting people down is the worst feeling. I think the only other alternative was to put out a record that we felt was mediocre. So it feels a little bit vindicating that people came out and bought [it] after we took the time to make the album that we wanted. So that feels really cool.''