Thicker playmats use a range of cores and surfaces: various foams (generic foam, PE/PE foam, EVA foam, polyethylene), padded polyester cores, and fabric or cotton top layers. Some models feature 100% organic cotton tops or recycled polyester. Many manufacturers also advertise non-toxic foam formulations and list free-from claims (PVC, BPA, lead, phthalates, latex, formamide).

Thicker playmats often include textured or grippy surfaces and play-focused features such as pop-out puzzle pieces, quilted or cloth-like tops, reversible prints, fold-up walls to create a play arena, detachable toys or pillows on activity mats, and cushioned surfaces designed for tummy time and crawling.

Many thicker playmats are modular: they use interlocking tiles or multi-tile sets (commonly 6- or 9-tile kits with border pieces). You can often connect multiple sets or tiles to expand the play area, and some seamless tile designs let you customize the mat's overall shape and size.

Some thicker playmats have water-repellent coatings or are advertised as water-resistant and easy to wipe clean. A few are machine-washable, but many only support spot cleaning or wiping. Several products warn that prolonged water exposure can damage the mat and recommend drying the mat thoroughly after any cleaning.

Age guidance varies by product: many list newborn or 0 months up through around 36 months, some use '0 months+' or 'All ages,' and certain activity mats specify 3 years and up.