Understanding the result
This calculator models a symmetrical corner cabinet whose front face lies across the two adjoining walls. It helps establish an approximate wall projection for a common triangular corner footprint. Built-in cabinets, curved fronts, chamfered backs and asymmetrical cupboards may require a measured plan or a full-size template.
- These results support research and planning; they do not independently establish authenticity, age or value.
- Keep direct observations separate from assumptions, seller claims and conclusions.
- Seek qualified, object-specific advice when the decision affects value, repair, safety or a legal transaction.
Good records improve research
Keep original observations separate from conclusions. Photograph the whole object and relevant details in even light; record dimensions, labels, maker marks, repairs, provenance and the references consulted. Do not alter the object just to obtain another clue.
Methodology and limitations
When depth is measured along the angle bisector from the corner to the front face, the idealised front width is 2 × depth × tan(angle ÷ 2). The wall projection on each side is depth ÷ cos(angle ÷ 2). The entered face width is compared with that idealised front width; discrepancies flag a nonstandard shape or inconsistent measurement.
For a 90° corner and a 40 cm bisector depth, the idealised front width is about 80 cm and the wall projection is about 56.6 cm on each side. A measured front width far from 80 cm suggests a different geometry or an inaccurate measurement.
Historical objects are often repaired, refinished, reassembled or made from more than one material. Modern reproductions may imitate older processes. A likely match should always be phrased as a research hypothesis unless it is supported by a qualified, object-specific assessment and trustworthy documentation.
Frequently asked questions
What does bisector depth mean?
It is the distance from the corner apex along the line that splits the corner angle into two equal halves, ending at the front face in this simplified model.
Does the formula work for a curved corner cabinet?
It gives only an approximate footprint. A curved front changes the relation between face width and wall projection; measure the outline or create a paper template.
Can I check whether the cabinet clears a skirting board?
Not from wall projection alone. Measure the skirting depth, cabinet feet and back shape separately, and include them in the installation plan.
Why compare calculated and measured front width?
For the symmetrical model, depth and angle imply a front width. A disagreement may indicate a nonstandard shape, a different depth measurement, or a measurement error.
Can the calculator prove the cabinet is original?
No. It is a geometry tool only and gives no evidence about date, maker or authenticity.
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