A drawer-first Gridfinity planner: measure the INSIDE of a drawer (width wall-to-wall, depth front-to-back, at the bottom), and it computes the largest grid of full 42mm Gridfinity cells that fits — then splits that grid into baseplate tiles sized to your printer bed and fills the leftover perimeter with smart spacer strips so nothing slides around. A 400×300mm drawer becomes a 9×7-cell floor: four plate tiles plus a ring of spacers, listed as an exact shopping list of what to print. The two measurements that matter are inside width and depth — measure twice, at the bottom of the drawer, past any runners or screw heads. Pick your printer so the splitter knows the bed (a 256mm Bambu bed carries 6 cells per side; the 2mm safety margin is why 252 ÷ 42 works out exactly). Use Front flush if you want the grid against the drawer front with all the leftover space at the back; Centered splits it evenly. Add 1–2mm of clearance if your drawer walls bow or your measurement is shaky — the grid shrinks a cell sooner, and the spacers still fill to the walls. Print tip: tiles print flat with no supports — the sockets are open through the bottom per spec. Print spacers in a contrast color and drop them in last; pieces under 1mm are skipped automatically as unprintable slivers. Bins click straight in from our Gridfinity Bins app (same parity-tested 42mm core). Workflow inspired by the True Gridfinity Drawer Creator (TUDC) on MakerWorld — the geometry here is our own spec-true Gridfinity core.