Flat Panel and Rectangular Opening Fit Calculator
Check whether a flat rectangle’s in-plane projection fits a rectangular opening at an angle from 0° to 90°.
YOUR CALCULATION
Result
—
Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Rotate the flat rectangle in its own plane. Its axis-aligned bounding dimensions are sine/cosine combinations of its sides. Intersect the angular ranges satisfying both usable opening dimensions.
Rotated bounding width=w cosθ+h sinθ; rotated bounding height=w sinθ+h cosθ
Worked example
A 120×40 cm flat rectangle does not fit unrotated in a 115×115 cm opening, but at 45° both projected dimensions are approximately 113.137 cm and fit this two-dimensional model.
Assumptions and input details
Two-dimensional static projection only. The result does not establish a three-dimensional moving route: panel thickness, out-of-plane tilting, doorway depth, approach space, corridors, handles and maneuvering are excluded. A no-fit result applies only to this in-plane model. Dimensions must be measured clear. Zero clearance and equality provide no physical tolerance. The diagram uses equal coordinate scales; when no fit exists it shows the unrotated projection.
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
Choose from 23 length definitions, including explicitly labelled regional measures. Area conversions square the length factor; geometric volumes cube it.
Regional measures are not interchangeable merely because their names look similar. This is a documented selection, not a claim to include every historical unit.
NIST measurement tables · Japanese traditional units · Mainland China and Hong Kong unit distinctions
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
Compare all six orientations for identical rectangular items in a rectangular container. Find the best uniform grid, counts along each axis and volume utilization.
Reflect, rotate or translate a point in the coordinate plane. Keep exact fractional coordinates and compare the original point with its image on equal-scale axes.
Find the diagonal of a right triangle or rectangle. Mix length units and compare 21 unit conversions with a triangle diagram.
Reserved advertising space.