180 seats is generally 29" in front of the over-wing exits and 28" behind the over-wing exits, assuming the rear toilets are forward of Doors 2.
177 on Jetstar (Australia-based 320s) is 30" due to 1 x rear lav placed where half the rear galley goes. This means one less row rear of the overwing exits compared to above configuration. In this config around seven rows forward of the over-wing exits on the DEF side are 29", to accommodate the forward bulkhead (which is galley side only).