Katy Perry and John Mayer are rumored to be planning to settle down and have a family.

The 30-year-old Perry has been in an on-again, off-again relationship with Mayer since they began dating in August 2012. After breaking it off twice earlier this year, the pair "are definitely back on," according to the New Zealand Herald.

"After their last breakup in July, John realised he made a mistake letting Katy go," an unnamed source said. "Katy wanted kids, and he wasn't ready, but now he's told her he's on-board."

However, apparently the 37-year-old "Your Body Is a Wonderland" singer wants to tie the knot before the couple decides to have a baby.

"Before they have a baby, John wants to be married. Getting married isn't as important to Katy, but since it is to John, they've talked about tying the knot by next summer," a source said.

Last month, the couple was seen holding hands while attending the wedding of their friends Allison Williams and Ricky van Veen in Wyoming.

"Being at Allison's wedding made Katy and John realise they've got something very special," a source told Life & Style. "They are ready to take things to the next level."

Perry previously married actor Russell Brand in October 2010, but they called off their relationship 14 months later.

The "Dark Horse" singer is winding down her long-running 151-date "Prismatic" world tour, which she kicked off in May 2014 and which has involved legs in Europe, North America and Australia. She played her most recent concert in Buenos Aires on Saturday night. Her last show, which is also part of the South American leg of her tour, will take place in Costa Rica on Sunday, Oct. 18.

Perry last released her fourth studio album, "Prism," in October 2013. The album produced the singles "Roar," "Unconditionally," "Dark Horse," "Birthday" and "This Is How We Do."