Cabinet Door Size Calculator

Cabinet Door Size Calculator

Required Door Dimensions:

function calculateCabinetDoors() { var width = parseFloat(document.getElementById('openingWidth').value); var height = parseFloat(document.getElementById('openingHeight').value); var overlay = parseFloat(document.getElementById('overlayAmount').value); var gap = parseFloat(document.getElementById('doorGap').value); var numDoors = parseInt(document.getElementById('numDoors').value); var resultDiv = document.getElementById('cabinetResult'); var output = document.getElementById('doorOutput'); var details = document.getElementById('calculationDetails'); if (isNaN(width) || isNaN(height) || isNaN(overlay) || width <= 0 || height <= 0) { alert("Please enter valid positive numbers for width and height."); return; } // Calculate height (always the same regardless of door count) var finalHeight = height + (overlay * 2); var finalWidth; var textDetails = ""; if (numDoors === 1) { finalWidth = width + (overlay * 2); output.innerHTML = "1 Door: " + finalWidth.toFixed(3) + "\" W x " + finalHeight.toFixed(3) + "\" H"; textDetails = "Calculation: Width (" + width + " + " + (overlay * 2) + " overlay) | Height (" + height + " + " + (overlay * 2) + " overlay)"; } else { // Formula: ((Opening Width + 2*Overlay) – Gap) / 2 finalWidth = ((width + (overlay * 2)) – gap) / 2; output.innerHTML = "2 Doors: " + finalWidth.toFixed(3) + "\" W x " + finalHeight.toFixed(3) + "\" H (each)"; textDetails = "Calculation: [(Width " + width + " + " + (overlay * 2) + " overlay) – " + gap + " gap] ÷ 2 doors"; } resultDiv.style.display = "block"; details.innerHTML = textDetails; }

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How to Use the Cabinet Door Size Calculator

Whether you are refacing old cabinets or building custom kitchen units from scratch, determining the correct door size is critical for both aesthetics and functionality. This calculator helps you determine the exact manufacturing dimensions for your doors based on your cabinet opening measurements.

Key Terms Explained

• Opening Width/Height: This is the inner measurement of the cabinet "hole" or frame where the items are stored.
• Overlay: This is how much the door overlaps the cabinet frame. A 1/2″ (0.5) overlay is the most common industry standard. If you want the door to cover more of the frame, you might use a 1-1/4″ overlay.
• Reveal/Gap: Essential for double doors. If you have two doors meeting in the middle, you need a small gap (usually 1/8″ or 0.125″) so they don't hit each other when opening and closing.

The Math Behind the Calculation

The standard formula for a single door with overlay is:

Door Width = Opening Width + (Overlay × 2) Door Height = Opening Height + (Overlay × 2)

For double doors (a pair), we must account for the center gap:

Individual Door Width = [(Opening Width + (Overlay × 2)) - Gap] ÷ 2

Real-World Examples

Example 1: Single Pantry Door
If your opening is 18″ wide and 30″ high with a standard 1/2″ overlay:
– Width: 18 + 0.5 + 0.5 = 19″
– Height: 30 + 0.5 + 0.5 = 31″
– Final Size: 19″ x 31″

Example 2: Double Kitchen Base Cabinet
If your opening is 30″ wide and 24″ high with a 1/2″ overlay and a 1/8″ gap:
– Total Overlay Width: 30 + 1 = 31″
– Subtract Gap: 31 – 0.125 = 30.875″
– Divide by 2: 15.4375″
– Final Size: Two doors at 15.438″ x 25″

Measurement Tips for Success

1. Measure Twice: Always measure the top, middle, and bottom of an opening. If the cabinet is slightly out of square, use the smallest measurement for width and height.
2. Check Hinge Specs: Ensure your hinges are designed for the specific overlay amount you enter (e.g., buy 1/2″ overlay hinges if you use 0.5 in the calculator).
3. Consider the "Clearance": If your cabinet is next to a wall, ensure the overlay doesn't cause the door to hit the wall when opening.