16 × 20 inch print at 150 DPI is 2400 × 3000 pixels

The working

Pixels are inches multiplied by the resolution.

• Width: 16 in × 150 = 2,400, which rounds to 2400 pixels.
• Height: 20 in × 150 = 3,000, which rounds to 3000 pixels.

Bleed is extra image past the trim line, so that a cut that lands slightly off still leaves ink to the edge. Print shops usually ask for 0.125 in on every side of a US size, which makes the file 2438 × 3038 pixels.

Is your photo big enough?

To fill 16 × 20 inch print at 150 DPI an image needs at least 2400 × 3000 pixels. Cropped to fill the sheet:

• A 12 megapixel phone photo (4000 × 3000) gives 188 DPI: enough.
• A 24 megapixel camera photo (6000 × 4000) gives 250 DPI: enough.
• A 48 megapixel photo (8000 × 6000) gives 375 DPI: enough.

At 150 DPI the pixels of a print blend together from about 22.9 inches (58 cm) away. 150 DPI is a common minimum for posters and large prints seen from a step or two away, and a usual setting for scanning documents that only need to be read.