Calculating Sq Ft

Square Footage Calculator

Standard for flooring is 10% to 15%.

Results:

Base Area: 0 sq. ft.

Total with Waste: 0 sq. ft.

(Equivalent to 0 sq. yards or 0 sq. meters)


How to Calculate Square Feet Correcty

Calculating square footage is a fundamental skill for home improvement projects, real estate, and interior design. Whether you are ordering hardwood floors, painting a bedroom, or measuring a lawn for sod, getting the numbers right prevents overspending or running out of materials mid-project.

The Basic Square Footage Formula

For a standard rectangular or square room, the formula is simple:

Area = Length (ft) × Width (ft)

Handling Inches in Your Measurements

Most rooms aren't perfect round numbers. If a room is 10 feet 6 inches long, you cannot simply multiply 10.6. You must convert the inches to a decimal of a foot by dividing by 12.

  • 6 inches = 6 / 12 = 0.5 feet
  • 3 inches = 3 / 12 = 0.25 feet
  • 9 inches = 9 / 12 = 0.75 feet

Therefore, 10 feet 6 inches becomes 10.5 feet.

Why Include a Waste Factor?

When ordering materials like tile, laminate, or carpet, professionals always recommend adding a "waste factor." This accounts for:

  • Cuts needed to fit corners and edges.
  • Accidental breakage or mistakes.
  • Natural variations in material (like knots in wood).

Common Waste Guidelines:
• Tile (Simple Pattern): 10%
• Tile (Diagonal/Herringbone): 15-20%
• Hardwood Flooring: 10%
• Carpet: 10%

Practical Example

Imagine you have a room that measures 12′ 4″ long and 15′ 8″ wide. You want to install tile and plan for a 10% waste factor.

  1. Convert to Decimals: 12′ 4″ = 12.33 ft. | 15′ 8″ = 15.67 ft.
  2. Calculate Base Area: 12.33 × 15.67 = 193.21 sq. ft.
  3. Add Waste: 193.21 × 1.10 = 212.53 sq. ft.
  4. Result: You should purchase at least 213 square feet of tile.
function calculateSquareFootage() { var lFt = parseFloat(document.getElementById('lenFt').value) || 0; var lIn = parseFloat(document.getElementById('lenIn').value) || 0; var wFt = parseFloat(document.getElementById('widFt').value) || 0; var wIn = parseFloat(document.getElementById('widIn').value) || 0; var waste = parseFloat(document.getElementById('wasteFactor').value) || 0; // Convert everything to decimal feet var totalLengthFeet = lFt + (lIn / 12); var totalWidthFeet = wFt + (wIn / 12); // Calculate Base Area var baseArea = totalLengthFeet * totalWidthFeet; // Calculate Total with Waste var totalWithWaste = baseArea * (1 + (waste / 100)); // Secondary Units var sqYards = totalWithWaste / 9; var sqMeters = totalWithWaste * 0.092903; // Display Results document.getElementById('baseArea').innerHTML = baseArea.toFixed(2); document.getElementById('totalArea').innerHTML = totalWithWaste.toFixed(2); document.getElementById('sqYards').innerHTML = sqYards.toFixed(2); document.getElementById('sqMeters').innerHTML = sqMeters.toFixed(2); document.getElementById('sqResultBox').style.display = 'block'; }

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