Free calculators
Interior Design Tools & Calculators
Plan your space with our free tools. From layout to lighting, get practical calculators built for real projects.
Use the category bar and search below to jump straight to the calculator you need — everything runs in your browser.
Free planning tools · No signup
Good design starts with the details.
Arrange & measure
Gallery wall planner
Arrange your frames. See the whole wall. Save a plan before you hang.
Find the right fit
Sofa size calculator
Find a sofa that fits your room, your seating needs and your walkways.
Get the proportions right
Rug size calculator
Compare rug sizes and find a balanced fit for your furniture.
Layout & furniture
Room flow, seating, and key dimensions before you buy or hang.
Floor Plan Maker
Draw a room and explore furniture in 2D and 3D
Furniture Layout Planner
Arrange furniture for optimal flow
Sofa Sizing Calculator
Find the perfect sofa size for your room
Coffee Table Calculator
Get proportional coffee table dimensions
TV Size Calculator
Optimal TV size based on viewing distance
Bathroom Layout Planner
Design functional bathroom layouts
Kitchen Layout Planner
Plan optimal kitchen layouts
Room Size Calculator
Calculate ideal room dimensions
Rugs & runners
Size rugs for living, dining, bedrooms, halls, stairs, and rounds.
Rug Size Calculator
Find the perfect rug dimensions
Living Room Rug Size
All-legs-on or front-legs-on layouts
Dining Room Rug Size
Rug under dining table with 24" rule
Bedroom Rug Size
Under-bed rugs or side runners
Hallway Runner Calculator
Ideal runner width, length, segments
Round Rug Size Calculator
Pick the right diameter for round rugs
Stair Runner Calculator
Calculate runner size for stairs
Materials
Quantities for paint, floors, and wall finishes.
Lighting
Lumens, daylight, and fixture choices.
Walls, color & style
Art, gallery walls, curtains, color, and finishing details.
Design Style Quiz
Discover your design style
Astrology Style Recommender
Style ideas inspired by astrological themes
Wall Art Calculator
Size artwork perfectly
Curtain Calculator
Calculate curtain dimensions
Color Scheme Generator
Create color palettes
Gallery Wall Calculator
Plan multiple artwork layouts
Picture Wall Layout Generator
Custom gallery wall layouts
Window Treatment Calculator
Size blinds and shades perfectly
Cabinet Hardware Calculator
Perfect knob and pull placement
Kitchen Island Calculator
Optimal island dimensions
Vanity Size Calculator
Perfect bathroom vanity size
Why use these tools?
Same math designers use — packaged so you can decide before you order or drill.
Accurate planning
Get precise measurements and calculations for your interior design projects.
Save time
Quick calculations and instant results help you make decisions faster.
Cost effective
Avoid over-ordering materials and optimize your budget.
Professional results
Get professional-grade calculations for your design projects.
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