Screen size converter
TV & Monitor Size: cm to Inches
Formula: inches = cm ÷ 2.54 · screen size is always the diagonal, never the width
Common TV & monitor sizes (16:9)
| Diagonal (in) | Diagonal (cm) | Width × Height (cm) |
|---|
Frequently asked
Is TV size measured diagonally or by width?
Always diagonally, corner to corner across the visible screen, not including the bezel. A “55 inch TV” has a 55-inch diagonal, not a 55-inch width — its actual width is closer to 48 inches on a 16:9 screen.
How many cm is a 55 inch TV?
A 55 inch screen converts to about 139.7 cm diagonally. On a standard 16:9 panel that works out to roughly 121.7 cm wide and 68.5 cm tall.
Why do two screens with the same inch size have different widths?
Because the inch or cm figure is only the diagonal. The actual width and height also depend on the aspect ratio, so a 27″ ultrawide monitor is noticeably wider and shorter than a 27″ standard 16:9 monitor.
How do I measure my screen myself?
Run a tape measure from one visible corner of the screen to the opposite corner, in a straight diagonal line, excluding the plastic bezel. Convert that cm reading above to get the inch “class” size.