Decide whether you want inside mount or outside mount
For inside mount, measure the exact width of the window opening at the top, middle, and bottom
Use the smallest width measurement for inside mount
For inside mount, measure the height of the window opening at the left, middle, and right
Use the longest height measurement for inside mount
Measure the window depth to ensure enough space for inside mount hardware
For outside mount, measure the full width you want the shade or blind to cover
For outside mount, add extra width beyond the window opening for better light control and coverage
For outside mount, measure the full height you want the shade or blind to cover
Decide how much overlap you want above and around the window
Measure in three places for width and height to account for uneven windows
Record measurements to the nearest 1/8 inch
Do not make any deductions unless the manufacturer instructs you to do so
Use a steel tape measure for accuracy
Measure each window separately
Double-check all measurements before ordering
Note any obstructions such as handles, locks, or trim
Confirm whether the shade or blind will be mounted inside the frame or on the wall or trim
Measure the exact location where brackets will be installed
Keep width and height measurements labeled clearly for each window
Follow the specific measuring instructions for the product you are ordering