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SMARTR SPACES · FREE 3D ROOM PLANNER

Home theatre calculator.
Your cinema, in 3D.

Plan your custom home theatre: seating, speaker placement, screen size and projector distance. Explore what fits, then see it come together.

DESIGNED AROUND YOUR ROOM

From the first seat to the final speaker.
A considered start to your private cinema.

A BIGGER CANVAS FOR YOUR IDEAS

Home Theatre Designer works best on a desktop.

Please open this configurator on a desktop or laptop for the complete 3D design experience.

Explore our home theatre services ↗

FROM ROOM MEASUREMENTS TO MOVIE NIGHT

A custom home theater, planned around you.

Start with the room you have. This free home theatre calculator helps you explore how a screen, recliners and an immersive speaker system fit together before you choose equipment. Change the dimensions, compare layouts and inspect your private cinema from your seat in 3D. No sign-up is needed.

Use the interactive designer on a desktop or laptop. On your phone, you can read the planning notes below and copy the link to continue on a larger screen.

Screen size & viewing distance

Compare projection screens and TVs against your room width, ceiling height and seating position. The calculator converts a screen diagonal and aspect ratio into image width and height, then checks space for the frame, speakers and floor clearance.

A 120-inch 16:9 image is approximately 2.66 m wide and 1.49 m high, before adding a frame. A screen that fits the wall may still feel too large from the front row, so the designer also reports the viewing angle. For a quick standalone check, try our screen size and viewing angle calculator.

Projector throw distance calculator

Explore long, short and ultra-short-throw categories alongside ceiling, wall, shelf and low mounting options. Technical Review shows the lens-to-image distance, required throw ratio and the selected category's distance range.

Throw distance equals image width multiplied by throw ratio. For example, a 2.66 m-wide image at a 1.5:1 ratio needs about 3.99 m between the lens and image plane. Category ranges are a starting point; the final projector must support the required ratio, lens offset and screen surface.

Surround sound & speaker placement

Compare surround and overhead speaker layouts using a chosen main listening seat. The tool checks placement angles, room clearances and separation, and explains why a larger layout may be unsuitable. Multiple subwoofers appear separately from amplified speaker channels.

Inspect left, centre and right speaker clearances around the image, or the cavity and enclosure-to-screen gaps behind an acoustically transparent screen. The technical table includes speaker coordinates and listening distances. Read our home theatre speaker layout guide for the wider setup process.

Recliner seating & room layout

Set seats per row, choose your listening position and explore rear-aligned or manually positioned seating. The planning model reserves at least six feet of depth per row for reclining and offers four, four-and-a-half or five-inch rises for later rows.

The 3D view shows those platforms so you can judge the arrangement. Actual recliner dimensions, sightlines and step access still need checking for your room. Try a dark cinema finish, turn on the starlit ceiling and open fullscreen to experience the atmosphere from your selected seat.

THE NEXT STEP, WITH CONFIDENCE

Before you build your home cinema

How do I use the home theatre room planner?

Enter width, length and height in feet or metres, then select the screen wall. Work through seating, audio, speaker style, display and projector. Technical Review explains measurements and warnings; Specification lets you save locally, copy a design link, download JSON or print the requirements for a design discussion.

Can I use it for a small home theater?

Yes. Start with your actual room dimensions and compare the options the tool allows. It limits seating rows, screen sizes and speaker layouts as space becomes tighter. Read the explanations beside each option: an available layout may still involve a compromise.

Does this calculate the cost of a custom home theatre?

It calculates a preliminary layout and equipment requirements. Pricing depends on the selected products, acoustic treatment, finishes, wiring and installation. Share your design with SmartR for a project discussion through our custom home theatre design and installation service.

Is the technical specification ready for installation?

Use it as a planning brief. The measurements use configurable guidance and representative equipment dimensions. A final design needs a site survey, exact product specifications, acoustic planning, sightline checks and installation review. Explore acoustic treatment and soundproofing alongside the equipment layout.

Make room for your cinema.

Try a layout, save your ideas and bring them to your design discussion.

Discuss your home theatre