How it works
What this tool calculates, and what it can’t
Where the numbers and verdicts on the plan come from, and how far to trust them.
Coordinates and area
The top-left corner of the room is (0, 0). x grows to the right, y grows downward. Every position and size is in centimeters, and every room is a rectangle.
Each piece of furniture is drawn as the rectangle around its outer edge. "Furniture" in the status bar is the sum of those rectangles inside the room. If two pieces overlap, the overlap gets counted twice, so the figure can be higher than the floor actually covered.
Overlap check
Rectangles A and B overlap when all four of these are true:
A.top < B.bottom · A.bottom > B.top
Edges that just touch don't count. Anything poking outside the room gets its own warning. Height is ignored, so a chair pushed under a desk or a storage box under a bed shows up as an overlap.
The 60 cm route check
The floor gets a dot every 10 cm. Dots closer than 30 cm to a wall or to any furniture are dropped. What's left are the places where the center of a 60 cm-wide person could stand.
Starting from the dot in front of the door (bottom wall, center), the search spreads to neighboring dots, up, down, left and right (a breadth-first search). Reach any dot in the top 28% of the room and the result is Connected. Otherwise it's Not found. If even the dot by the door is blocked, the planner says so separately.
Because the dots are 10 cm apart, the check can be up to about 10 cm stricter than reality. The 60 cm route note walks through a case where a 63 cm gap fails. The buffer around furniture is square-cornered, so pieces staggered on a diagonal also look closer together than they are.
What isn’t modeled
- Where your real door is, and which way it swings. The planner's door is always 80 cm, centered on the bottom wall.
- Windows, built-ins, columns, baseboards, radiators, pipes and outlets
- Furniture height, handles, and drawers or doors that stick out when opened
- Walking diagonally, or turning around
Reading the numbers on this site
What the figures around the site are, and aren't, all in one place.
- Default furniture sizes. The sizes in the list are typical examples. Products vary, so swap in the outside dimensions of whatever you're buying.
- Rooms in the layout notes. Room sizes and furniture coordinates in the notes are worked examples built to show the math. They aren't measurements of real homes.
- The 60 cm path and 80 cm door. Benchmarks chosen for this site, not taken from building codes, fire codes or accessibility standards. A Connected result doesn't mean a layout is safe or comfortable.
- Rough figures in the notes. Things like wardrobe door clearance or monitor stand depth are based on typical products. The product's own instructions take priority.
- What a result means. Drawings and checks are calculated from the numbers you enter, nothing more. They aren't installation or safety advice, so measure again before you buy or move anything in.
Reopening the drawings
Every layout note lists the room size and furniture coordinates in the text. The "Open original" and "Open revised" buttons load those exact coordinates into the planner. The drawings in the notes come from the same calculation code as the planner, so the verdicts match. No photos or generated images are used.
Real-world reference
The 105 × 50 cm desk matches the size listed on IKEA's MICKE desk product page. No prices or stock information are given.
Where data is stored
Your layout is saved in the browser's localStorage. There are no accounts, and layouts aren't uploaded anywhere. "Copy link" creates a URL with the room size and layout encoded inside it; anyone you send it to can see the same plan.
If a calculation looks wrong or a number in a note doesn't add up, please get in touch. Include the room size and furniture coordinates and I can reproduce it right away.