About FlatPlanner

Laying out a room looks simple until you start putting numbers to it. How many square feet is a space that isn’t a perfect rectangle? How many boxes of flooring do you buy once you allow for offcuts and a diagonal pattern? Does one can of paint cover the walls, or two, and does that change on bare plaster? Will a sofa and chairs leave enough room to walk past without turning sideways? What size rug actually sits right under a bed or a dining table? And when a plan is drawn at 1:50, how wide is that doorway in real life? None of these are hard once you know the method — but working them out by hand, on every room, is exactly where planning a layout turns into a chore.

FlatPlanner is built around that gap. Rather than long articles you have to read end to end, the site is a set of small, single-purpose calculators, each aimed at one real decision. The Room Area & Square Footage Calculator turns length and width — or several rectangles added together — into a floor area you can plan and price against. The Flooring Material Calculator takes that area, adds a waste allowance for cuts and pattern matching, and works out how many planks, tiles, or boxes to order. The Paint Quantity Calculator estimates litres or gallons from wall area, coats, and a coverage rate, with door and window openings subtracted. The Furniture Clearance & Walkway Planner checks whether a sofa and chairs, a bed, or a table leave sensible walkways and passing room around them. The Rug Size Calculator suggests a rug footprint that suits the room and the furniture that sits on or around it. And the Floor Plan Scale Converter moves between a measurement on a drawing and its real-world size at any scale, so you can read a plan or draw one to the right ratio.

Alongside the calculators, the blog and learnsection explain the reasoning the tools rest on — how to measure an irregular room and break it into rectangles, why a waste factor matters and how pattern and diagonal layouts raise it, how paint coverage shifts with surface porosity and the number of coats, and how architectural scales translate a small drawing into a full-size space. The museum collects notable floor plans and layout ideas to browse for reference.

A few things worth stating plainly. FlatPlanner is independent and not affiliated with any retailer, manufacturer, contractor, or authority. It is supported by advertising, which is how the tools stay free with no account required. The calculators run in your browser, so the figures you enter never leave your device. Every result a tool produces — a floor area, a box count, a paint quantity, a clearance check, a rug size, a scaled dimension — is a general estimate based on the numbers you enter and on common formulas, meant for planning only. It is not professional design, engineering, architectural, or construction advice. Measurements taken off a plan can differ from what you find on-site, so always confirm dimensions in the room itself, and consult a qualified professional or contractor before anything load-bearing, permit-related, or costly. If a tool looks wrong, or there’s a calculator you wish existed, the contact page is the place to tell us.