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TV Inches to Width & Height

Inches measure the diagonal. At 16:9 the width is 0.871× the diagonal and the height 0.49× — a 55-inch set is 121.8 cm by 68.5 cm.

Your numbers

Length

121.8cm

Width

68.5cm

Area

8,339cm²

Formula

Length = Inches × 2.54 × Aspect width ÷ √(Aspect width² + Aspect height²)

Bezels and stands are not included — check the outer dimensions before fitting it into furniture.

What to enter

InputDefaultAccepted range
Inches (in)The diagonal in inches — screens are always named by the diagonal.551 and up
Aspect widthThe width part of the aspect ratio — the 16 in 16:9.161 and up
Aspect heightThe height part of the aspect ratio — the 9 in 16:9.91 and up

Step by step

FormulaLength = Inches × 2.54 × Aspect width ÷ √(Aspect width² + Aspect height²)
With the default numbersLength = 55 × 2.54 × 16 ÷ √(16² + 9²)
AnswerLength = 121.8 cm

Quick reference table

Results when only Inches (in) changes and everything else stays put.

Inches (in)Length (cm)Width (cm)Area (cm²)
27.560.934.22,085
41.391.451.44,702
55121.868.58,339
82.5182.6102.718,763
110243.513733,357

What each result means

ResultAt default values
Length (cm)The measurement across, side to side.121.8
Width (cm)The measurement front to back.68.5
Area (cm²)The space a shape covers — length squared.8,339

Common mistakes

Bezels and stands are not included — check the outer dimensions before fitting it into furniture.

Glossary

Inches
The diagonal in inches — screens are always named by the diagonal.
Aspect width
The width part of the aspect ratio — the 16 in 16:9.
Aspect height
The height part of the aspect ratio — the 9 in 16:9.
Length
The measurement across, side to side.
Width
The measurement front to back.
Area
The space a shape covers — length squared.

Frequently asked questions

Q. How is TV Inches to Width & Height calculated?

Length = Inches × 2.54 × Aspect width ÷ √(Aspect width² + Aspect height²) — Inches measure the diagonal. At 16:9 the width is 0.871× the diagonal and the height 0.49× — a 55-inch set is 121.8 cm by 68.5 cm.

Q. Can you walk through an example?

With Inches 55in, Aspect width 16, Aspect height 9, the answer is Length 121.8cm.

Q. What do I need to enter?

Enter Inches, Aspect width, Aspect height. The result recalculates as you type, and an empty box counts as zero.

Q. How much does the answer move if I change a number?

Changing only Inches (in) moves the answer to Inches (in) 27.5 → Length (cm) 60.9 and Inches (in) 110 → Length (cm) 243.5. The table below lays out five steps.

Q. How are the numbers rounded?

Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.

Q. Anything to watch out for?

Bezels and stands are not included — check the outer dimensions before fitting it into furniture.

Related calculators

Keep your length units consistent across inputs — mixing centimetres and metres throws results far off.