You can tell your baby is growing up fast, but now you can know exactly how fast! That’s thanks to the Nanit Smart Crib Sheets, which measure your infant’s height while they’re in their bed. In fact, these smart crib sheets let you track all your baby’s growth spurts right from home. It works with the Nanit Camera, which detects the pattern on the Nanit Smart Sheets. Then, you can use the connected app to measure your little one and track their development. Made of 100% cotton, these super-soft sheets fit any standard crib, and they are easy to wash when necessary. Simply toss them in the machine, and they’ll be fresh and clean. They don’t contain any electronics at all, so they’re totally safe for baby to sleep on.