18 x 24 Inches to Pixels

18 × 24 inches is 5,400 × 7,200 pixels at 300 DPI, 2,700 × 3,600 pixels at 150 DPI and 1,728 × 2,304 pixels at the 96 PPI screen standard.

PPI
Size in inches
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Edit any field to convert a different size at the same resolution.

18 × 24 inches in pixels at every common resolution

The pixel count changes with the resolution you are working to — these are the values you are most likely to need.

18 × 24 inches to pixels (pixels = inches × DPI)
ResolutionWidth × height in pixelsTypical use
72 DPI1,296 × 1,728Legacy web
96 DPI1,728 × 2,304Screen and CSS
150 DPI2,700 × 3,600Posters and drafts
300 DPI5,400 × 7,200Photo and magazine print
600 DPI10,800 × 14,400Fine art and line work

How the conversion works

Pixels are found by multiplying the length in inches by the pixel density: pixels = inches × DPI. For 18 × 24 inches at 300 DPI that is 18 × 300 = 5,400 and 24 × 300 = 7,200.

18 × 24 inches is a common poster size.

Hung and read from about a metre away, 150 to 200 DPI is indistinguishable from 300, so 2,700 × 3,600 pixels is usually all it needs rather than the 5,400 × 7,200 a 300 DPI file would carry.

That works out at 38.9 megapixels at 300 DPI, or 9.7 megapixels at 150 DPI. In metric the same size is 45.72 × 60.96 cm.

Frequently asked questions

How many pixels is 18 × 24 inches, a common poster size?

5,400 × 7,200 pixels at 300 DPI, 2,700 × 3,600 at 150 DPI and 1,728 × 2,304 at the 96 PPI screen standard. Multiply the inches by whichever density you are working to.

How many pixels is 18 × 24 inches at 300 DPI?

5,400 × 7,200 pixels. That is the standard density for photographic and magazine printing.

What is 18 × 24 inches in centimetres?

45.72 × 60.96 cm, because one inch is exactly 2.54 centimetres.

Does this size really need 300 DPI?

Usually not. Something this size is read from about a metre away, and at that distance 150 to 200 DPI is indistinguishable from 300. That is 2,700 × 3,600 pixels rather than 5,400 × 7,200 — a quarter of the file for no visible loss.

Is 18 × 24 a 3:4 ratio?

Yes. That is 3:4, which is not a standard print shape: the closest is a Letter page, and fitting it means losing about 3% along the long edge.

Why does the pixel count change with DPI?

A pixel has no fixed physical size. The DPI value says how many pixels fill one inch, so raising it raises the pixel count needed to cover the same physical space.