All of our mat dimensions are detailed below. We recommend taking measurements of your tray prior to placing your order. Tiny Bowl At 9" wide and 6.5" tall, the Tiny Bowl is designed to fit on the tiniest of highchair trays, including the Stokke Tripp Trapp and Boon Flair trays. Mini Mat At 10.75" wide and 7.75" tall the Mini Mat is designed to fit on most highchair trays (even 'space saver' models). The Mini Mat does not fit on the following highchair trays: the Stokke Tripp Trapp, the Boon Flair, the Nuna Zaaz, the Keekaroo, the Ingenuity ChairMate (Easton), the Safety 1st Beaumont, and the Abiie Beyond Wooden Highchair. The high-gloss finish of the Oxo Sprout Highchair hinders the Mini Mat's suction feature. Mini Bowl At 8.5" wide and 7" tall, the Mini Bowl is designed to fit on most highchair trays (even 'space saver' models). The Mini Bowl does not fit on the Stokke Tripp Trapp or the Boon Flair tray. Happy Mat At 14" wide and 9" tall the Happy Mat does not fit on most highchair trays. We recommend removing the tray and pushing your highchair up to the table so the whole family can enjoy mealtime together. Happy Bowl At 10.25" wide and 8.75" tall the Happy Bowl will most likely fit on your highchair tray. If you have a 'space saver' model the Happy Bowl will not fit.