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WINDOW BLINDS / TOOL

Inside-mount blind measurement helper

Enter three width readings and three height readings to organize your order worksheet. This follows a common manufacturer method, not every blind model.

Record measurements by product

Enter inches; fractions may be entered as decimals (35 1/8 = 35.125).

Narrowest measured width35 in
Longest measured height (some products)58.125 in
Shortest measured height (other products)58 in
Not an order dimension.

Select a product type and calculate. Confirm the current manual before ordering.

Measure the recess at top, middle and bottom for width; record left, center and right heights. Use the rule for your exact blind model.
Measurement reference: Measure the recess at top, middle and bottom for width; record left, center and right heights. Use the rule for your exact blind model. Schematic, not to scale.

Why use three measurements?

Wood, plaster and trim can taper within one opening. A single width at the center can overestimate the space the blind must fit. Compare the three widths and record the smallest; compare all three heights, then apply the height rule specified for your exact treatment model. For example, some horizontal shades require the longest height, while vertical and banded treatments may require the shortest.

Manufacturer guidance

Read the LEVOLOR PREMIER 2025 general measuring guidelines (PDF, LPGI-19) and verify the instructions for your actual model. This tool cannot determine whether your recess is deep enough to fit an inside-mount headrail.

Worked six-reading example — geometry versus order size

Suppose top/middle/bottom widths are 35 1/8, 35, and 35 1/16 inches, and left/middle/right heights are 58, 58 1/8, and 58 inches. The narrowest observed width is 35 inches; the shortest and tallest heights are 58 and 58 1/8 inches. These are measurements, not an automatically approved blind order. A supplier may require the top width, minimum width, maximum height or minimum height for a particular SKU.

Before submitting a made-to-measure order

  1. Save all six readings with units, date and the surface you measured. Do not replace originals with rounded order numbers.
  2. Identify the exact brand, series, mount type, bracket depth and whether a protruding handle restricts movement.
  3. Open the product's current measuring sheet and confirm which reference reading to use; the document-conflict comparison shows why a generic method can fail.
  4. Check whether the supplier performs factory deductions and whether fabric width differs from headrail width. Never subtract an extra clearance allowance unless explicitly instructed.
  5. For homes with children, use appropriately compliant cordless coverings where applicable; a precise order dimension does not solve a cord hazard.