Size Comparison Tool: Screens and Rectangles Side by Side

Compare two sizes

Choose Screens to compare displays by diagonal and aspect ratio, or Rectangles for anything else with a width and height: paper, beds, rugs, tables, boxes, rooms. The drawing is to scale and overlays both shapes from the bottom-left corner.

The rectangle mode starts with US Letter (A) against A4 (B): A4 is narrower and taller, and 3.4% larger overall. It also tells you whether one shape fits inside the other, including after a 90° turn, which answers questions like whether a rug fits a room or a print fits a frame.

Why area is the honest comparison

Most products are named by one number: a TV's diagonal, a pizza's diameter, a mattress's width. But what you see, eat or sleep on is an area, and area grows with the square of the size. A size that is 10% larger in every direction has 21% more area, and a size that is 41% larger in every direction has double the area.

The last column answers the reverse question. "How much bigger" and "how much smaller" give different percentages because each uses a different starting size, which is why a jump from 55 to 65 inches feels larger than the 10-inch label suggests. Full dimensions for each size are in the TV size guide.

55-inch 47.9 × 27 in65-inch 56.7 × 31.9 in75-inch 65.4 × 36.8 in

16:9 screen sizes: width, height and area

Every current TV and most monitors use 16:9, so their width is 0.8716 × the diagonal and their height is 0.4903 × the diagonal. Use this table to compare screens without the tool.

These are screen (viewable area) dimensions. The TV or monitor itself is larger by its bezel (a fraction of an inch per side on most current models) and taller again on a stand.

Comparing screens with different aspect ratios

The diagonal only works as a comparison when both screens have the same shape. A wider screen spends more of its diagonal on width, so it ends up shorter than a 16:9 screen with the same diagonal. Compare height for documents and video, and width for multitasking.

Two things stand out. A 27-inch 16:9, a 34-inch ultrawide and a 49-inch super ultrawide are all about 13.2 in tall: the larger numbers only buy width. And a 12.9-inch 4:3 tablet has more screen area than a 13.3-inch 16:9 laptop despite its smaller diagonal. For the shapes behind these numbers, see aspect ratios explained; for desk fit, the monitor size guide.

Comparing round things: pizzas, tables, pots

For circles the area is π × (diameter ÷ 2)², so the same squaring applies. The rectangle mode does not handle circles, but the arithmetic is quick.

The same rule sets the capacity of round tables (a 60 in round table has 44% more surface than a 50 in one) and the base area of pans. The pizza size guide has a price-per-inch calculator for orders.

Everyday size comparisons

These are the pairings that come up most often, with the standard dimensions of each and the real difference in area.

The king against California king row is a good example of why area alone is not enough: the two beds cover almost the same floor, but one suits wide rooms and couples, the other tall sleepers and narrow rooms. The mattress size chart covers the room sizes each one needs.

Mistakes that skew size comparisons

• Comparing diagonals across shapes. A 34-inch ultrawide is not "7 inches bigger" than a 27-inch monitor in any direction that matters for height. Compare width and height.
• Mixing nominal and actual sizes. A 2 × 4 board is 1.5 × 3.5 in, an 8 in brick is 7 5/8 in long, and a "65-inch class" TV may have a 64.5 in diagonal. Compare the actual figures.
• Mixing inside and outside dimensions. Boxes, drawers, ovens and refrigerators have usable interiors several inches smaller than their exteriors.
• Forgetting orientation and clearance. A shape that fits on paper may need room to swing a door, walk around or tilt through a doorway. Add the clearance before you compare.
• Converting area with a length factor. 1 m² is 10.764 sq ft, not 3.28. Convert the sides first, then multiply.

Frequently asked questions