Square Footage Calculatorv1.0.0

Use this Square Footage Calculator to measure one room or an entire floor plan, convert results across imperial and metric units, and estimate the total cost of a project. Each room is independent, so you can mix shapes, units, and quantities in a single calculation. Follow these steps to produce accurate area and budget figures for construction, flooring, landscaping, painting, and renovation planning.

1. Click + Add Room / Area for every distinct space you want to measure. Give each room a clear name so the per-room breakdown is easy to scan and share with crews or clients.
2. Pick a shape from the room dropdown: Rectangle, Square, Circle, Oval or Ellipse, Triangle, Trapezoid, Rectangle Border, Circle Border, Annulus, L-Shape, Irregular Polygon, or Direct Area for a value that has already been measured.
3. Enter the dimensions the chosen shape requires. Fractions such as 3/8 and decimal values are both accepted. Each input has its own unit picker, so a single room can combine feet and inches without manual conversion. Supported linear units include microinches, inches, feet, yards, miles, micrometers, microns, millimeters, centimeters, meters, and kilometers.
4. For an Irregular Polygon, enter the boundary as x,y coordinate pairs on separate lines, walking the perimeter in order. The shoelace formula calculates the enclosed area for any convex or concave outline.
5. Set Quantity on a room to repeat identical spaces, such as four matching panels or three identical tiles. The area for that room is multiplied by the quantity before it is added to the total.
6. Open Optional Cost Calculation, select a currency, enter Cost per unit area, and choose the pricing area unit. The calculator multiplies the combined area by your unit price to produce a project total.
7. Review the per-room breakdown and the combined total across square feet, square inches, square yards, square meters, square centimeters, square millimeters, square kilometers, square miles, square micrometers, square microns, square microinches, acres, and hectares. Click Calculate to refresh, or Clear All to reset every field and start a new estimate.

Each shape uses standard geometric formulas. All inputs are converted to meters first, calculated in square meters, and then converted to every supported area unit.

• Rectangle and Square: Area = Length × Width (Square uses Side × Side)
• Circle: Area = π × (Diameter ÷ 2)²
• Oval or Ellipse: Area = π × (Major ÷ 2) × (Minor ÷ 2)
• Annulus: Area = π × ((Outer ÷ 2)² − (Inner ÷ 2)²)
• Rectangle Border: Area = (L + 2B)(W + 2B) − LW
• Triangle (Heron): Area = √[ s × (s − a) × (s − b) × (s − c) ], where s = (a + b + c) ÷ 2
• Trapezoid: Area = ((Base1 + Base2) ÷ 2) × Height
• L-Shape: Area = (Overall L × Overall W) − (Cutout L × Cutout W)
• Irregular Polygon (Shoelace): Area = ½ |Σ (xᵢ · yᵢ₊₁ − xᵢ₊₁ · yᵢ)|

Apply the Square Footage Calculator across trades, design tasks, and planning workflows where accurate area numbers drive material budgets, schedules, and quotes. The multi-room layout makes it easy to assemble whole-project totals without juggling several single-shape tools.

Plan building footprints, walls, ceilings, and roof sections with precise square footage. Produce takeoffs that reduce overbuying, schedule crews against accurate coverage numbers, and present clear breakdowns to clients across multiple rooms or zones in a single estimate. Combine standard rectangles with L-Shape and Trapezoid sections to capture real-world floor plans without rounding to a simple shape.

Measure carpet, tile, laminate, hardwood, and vinyl plank areas room by room. Include borders for thresholds and stair nosing, then convert totals to square meters or square yards for international quotes. Use the quantity field to estimate repeat installations across identical units, and adjust the pricing area unit to compare suppliers that quote in different conventions.

Calculate patios, walkways, lawns, mulch beds, and decorative rings with Circle, Oval, Annulus, and Irregular Polygon. Estimate pavers, sod, gravel, edging, and topsoil for plots measured in acres or hectares. Capture irregular lot boundaries from survey data by entering the perimeter as x and y coordinate pairs, and let the shoelace formula compute the enclosed area.

Compute wall and fence coverage, including triangular gables and trapezoidal sections. Add each surface as its own room, then plan primer, paint, sealant, or stain quantities for one or more coats. Adjust unit costs to compare premium and standard product options side by side without re-entering any measurements.

Verify room sizes for listings, appraisals, and inspections. Cross-check floor plans, capture irregular lot boundaries, and present clear area breakdowns to buyers, tenants, and contractors. Convert numbers between imperial and metric units to match the conventions used in each market or jurisdiction.