Curtain Length Calculator

Curtain Length Calculator

Use this calculator to determine the ideal finished length for your curtains, accounting for rod placement, desired hem style, and fabric allowances.

Measure from the top of your curtain rod (where the fabric will hang from) straight down to the floor.

Just Touching Floor (0 inches clearance) Floating (1/2 inch above floor) Puddling (2 inches extra on floor) Custom Clearance (specify below) Choose how you want your curtains to fall relative to the floor.

Enter a positive value for floating above the floor, or a negative value for puddling on the floor.

Extra fabric needed for the top finish (e.g., rod pocket, grommet heading, or for rings/clips). This is usually 2-4 inches.

Extra fabric needed for the bottom hem. A standard deep hem is often 4 inches.

// Initial call to set custom hem visibility on page load window.onload = function() { toggleCustomHem(); }; function toggleCustomHem() { var hemStyle = document.getElementById('hemStyle').value; var customHemDiv = document.getElementById('customHemClearanceDiv'); if (hemStyle === 'custom') { customHemDiv.style.display = 'block'; } else { customHemDiv.style.display = 'none'; } } function calculateCurtainLength() { var rodHeightFromFloor = parseFloat(document.getElementById('rodHeightFromFloor').value); var hemStyle = document.getElementById('hemStyle').value; var topHemAllowance = parseFloat(document.getElementById('topHemAllowance').value); var bottomHemAllowance = parseFloat(document.getElementById('bottomHemAllowance').value); var customHemClearance = parseFloat(document.getElementById('customHemClearance').value); var hemAdjustment = 0; var errorMessage = "; if (isNaN(rodHeightFromFloor) || rodHeightFromFloor <= 0) { errorMessage += '

"Rod Height from Floor" must be a positive number.

'; } if (isNaN(topHemAllowance) || topHemAllowance < 0) { errorMessage += '

"Top Hem Allowance" must be a non-negative number.

'; } if (isNaN(bottomHemAllowance) || bottomHemAllowance < 0) { errorMessage += '

"Bottom Hem Allowance" must be a non-negative number.

'; } if (hemStyle === 'custom' && isNaN(customHemClearance)) { errorMessage += '

"Custom Hem Clearance" must be a valid number.

'; } if (errorMessage !== ") { document.getElementById('curtainLengthResult').innerHTML = 'Please correct the following errors:

' + errorMessage + '

'; return; } switch (hemStyle) { case 'touching': hemAdjustment = 0; break; case 'floating': hemAdjustment = 0.5; // 0.5 inch above floor break; case 'puddling': hemAdjustment = -2; // 2 inches extra on floor (negative because it adds to length) break; case 'custom': hemAdjustment = customHemClearance; break; } var totalCurtainLength = rodHeightFromFloor – hemAdjustment + topHemAllowance + bottomHemAllowance; document.getElementById('curtainLengthResult').innerHTML = '

Calculated Curtain Length:

Your ideal curtain length is: ' + totalCurtainLength.toFixed(1) + ' inches.(This is the total fabric length needed for one panel, including hems.)'; }

Understanding Curtain Length: A Comprehensive Guide

Choosing the right curtain length is crucial for achieving a polished and professional look in any room. Curtains that are too short can make a window appear awkward and unfinished, while those that are excessively long might look messy or become a tripping hazard. This guide, along with our Curtain Length Calculator, will help you master the art of curtain measurement and selection.

Why Does Curtain Length Matter?

• Aesthetics: Correctly sized curtains enhance the visual appeal of your windows and the entire room. They can make a ceiling appear higher or a window feel grander.
• Functionality: Proper length ensures curtains can effectively block light, provide privacy, and offer insulation when needed.
• Style: Different curtain lengths contribute to distinct design styles, from modern and crisp to romantic and luxurious.
• Safety: Especially important in homes with children or pets, avoiding excessively long, pooling curtains can prevent accidents.

How to Measure for Curtains: Step-by-Step

Accurate measurement is the foundation of perfectly hung curtains. Here's how to get the numbers for our calculator:

1. Determine Your Rod Placement

Before measuring, decide where your curtain rod will be installed. For a more expansive look, rods are typically mounted 4-6 inches (or even more) above the window frame and extend 6-12 inches beyond the frame on each side. The higher and wider you go, the larger your window will appear.

Measurement for Calculator: "Rod Height from Floor"

• Using a metal tape measure, stand at the exact spot where your curtain rod will be installed (or is already installed).
• Measure straight down from the very top of the rod (or the top of the ring/grommet if that's where the fabric starts) to the floor.
• Record this measurement in inches.
• Example: If your rod is 90 inches from the floor, enter '90'.

2. Choose Your Desired Hem Style

The way your curtains meet the floor (or sill) significantly impacts the room's style. Consider these popular options:

• Floating (1/2 inch above floor): This is a clean, modern look that prevents curtains from dragging or collecting dust. It's practical for high-traffic areas and easy to open and close. Our calculator uses 0.5 inches for this style.
• Just Touching Floor (0 inches clearance): A classic and elegant choice, where the curtain hem barely skims the floor. It offers a tailored appearance and good light blockage. Our calculator uses 0 inches for this style.
• Puddling (2 inches extra on floor): For a luxurious, romantic, or traditional feel, curtains can "puddle" on the floor. A slight puddle (1-3 inches) is common. Our calculator uses 2 inches for a standard puddle.
• Sill Length: Curtains that end at the windowsill. Best for windows above radiators or furniture, or in kitchens/bathrooms where long curtains are impractical. (Note: This calculator focuses on floor-length curtains. For sill length, measure from the rod to the sill and add hem allowances.)
• Apron Length: Curtains that extend a few inches (typically 4-6 inches) below the windowsill. Offers a slightly softer look than sill length. (Note: Similar to sill length, this calculator is optimized for floor-length.)
• Custom Clearance: If you have a specific clearance in mind (e.g., 1 inch floating, or 4 inches puddling), you can input your own value. Remember, a positive value means floating *above* the floor, and a negative value means *extra fabric* for puddling.

Measurement for Calculator: "Desired Hem Style" or "Custom Hem Clearance"

• Select one of the predefined styles or enter your custom value.
• Example: For a floating look, select 'Floating'. If you want 3 inches of puddle, select 'Custom' and enter '-3'.

3. Account for Top Hem Allowance

This is the extra fabric needed at the top of your curtain panel to create the heading style (e.g., rod pocket, grommets, pleats, or for attaching rings/clips). This allowance ensures the finished curtain hangs correctly from the rod.

Measurement for Calculator: "Top Hem Allowance"

• Rod Pocket: Typically 2-4 inches, depending on rod diameter and desired ruffle.
• Grommets: Usually 2-3 inches above the grommet hole.
• Rings/Clips: Often 1-2 inches above where the ring/clip attaches to the fabric.
• Pleated Curtains: The heading itself is usually 3-4 inches, plus seam allowance.
• Consult your curtain pattern or manufacturer's instructions for precise recommendations. A common default is 2 inches.
• Example: For a standard rod pocket, enter '2'.

4. Account for Bottom Hem Allowance

The bottom hem provides weight and a finished look to your curtains. A generous hem often helps curtains hang better.

Measurement for Calculator: "Bottom Hem Allowance"

• Standard bottom hems are usually 3-4 inches.
• For a more luxurious or weighted look, you might go up to 6-8 inches.
• Enter your desired bottom hem allowance in inches. A common default is 4 inches.
• Example: For a standard deep hem, enter '4'.

Using the Curtain Length Calculator

Once you have these measurements, simply input them into the calculator above. It will provide you with the total fabric length needed for each curtain panel, from the very top edge of the fabric to the finished bottom edge, including all allowances.

Realistic Example:

• Rod Height from Floor: 90 inches
• Desired Hem Style: Floating (1/2 inch above floor)
• Top Hem Allowance: 2 inches
• Bottom Hem Allowance: 4 inches
• Calculation: 90 (rod height) – 0.5 (floating) + 2 (top hem) + 4 (bottom hem) = 95.5 inches.
• This means you would need to cut your fabric panels to 95.5 inches in length before sewing.

Important Considerations

• Fabric Shrinkage: Always pre-wash and dry your fabric according to its care instructions before cutting and sewing, especially if it's a natural fiber like cotton or linen, to account for shrinkage.
• Lining: If you plan to line your curtains, remember that the lining fabric will also need to be cut to the same finished length as your main curtain fabric, plus its own hem allowances if sewn separately.
• Pattern Matching: If your fabric has a large pattern repeat, you'll need extra yardage to ensure patterns align across panels. This calculator determines length, not total yardage.
• Double-Check: Measure twice, cut once! It's always a good idea to double-check your measurements before making any cuts.

By following these guidelines and utilizing the Curtain Length Calculator, you'll be well on your way to creating beautiful, perfectly fitted curtains that elevate your home decor.