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Interior Redesign AI
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Free room planning calculators

5 free planning calculators for furnishing a room: TV size for your seat distance, lumens per room, walkway and coffee table clearances, dining table size by seats, and curtain width and length. Each tool applies a published standard and shows the math.

Updated · By the Interior Redesign AI editorial team · Sources cited on the page

The same living room furnished in a light Scandinavian style: grey sofa, wood coffee tables and a patterned rug

Layout and furniture

Clearances, table sizes and curtains that fit.

Furniture Clearance PlannerPass or fix checks for coffee table gaps, walkways, bed sides and dining chairs.Free, no sign-upDining Table Size CalculatorTable size by seats and shape, and the largest table your room fits with clearance.Free, no sign-upCurtain Size CalculatorRod width and height, panel width with fullness, and the standard length to buy.Free, no sign-up

Screens and light

TV size, viewing distance and lumens.

TV Size and Viewing Distance CalculatorScreen size for your seat distance (and back), by the 30° and 40° viewing angles.Free, no sign-upLumens Calculator by RoomLumens and bulbs for any room from IES footcandle targets and its floor area.Free, no sign-up

How we calculate

Each tool does plain, visible arithmetic in your browser, with no AI and no server call, and shows its formula, a worked example and its sources on the page. Code figures cite the model code section, quantities cite the manufacturer's published spec, and prices cite a named cost guide with the date we checked it.

Where we had to assume something, the page says so and the widget lets you change it. Results are planning numbers, not quotes or code rulings.

More tools for this project

Then see it on your room

The same photo, before and after an AI render. Your walls, windows and layout stay; the finishes change.

An empty living room with light oak floors, white walls and a tall window
Before
The same living room furnished in a light Scandinavian style: grey sofa, wood coffee tables and a patterned rug
After: Light Scandinavian (AI illustration)

Questions

Are these planning tools free?

Yes. They run in your browser, cost nothing and need no account. Only the AI redesign of your own room photo needs a free account.

Where do the rules come from?

From published standards and guides: SMPTE and THX viewing angles for TVs, IES-based light levels for lumens, NKBA clearances for walkways and seating, and maker guides for curtains. Each page links its sources.

Are the results strict rules?

No. They are starting points from published guidance. Your room, your eyes and how you use the space decide the final call.