When printing photos, you will notice that you will be choosing from a set of a few standard sizes. While the U.S. has its own standard photo printing sizes, these sizes also comply with worldwide printing sizes. Standard photo printing sizes make it easier to purchase frames worldwide for your photos. The digital age has created new standards for photo printing, using PPI and DPI, pixels per inch and dots per inch. PPI effects the size of your photo, while DPI effects the definition. Different digital resolutions can produce standard photos or photos for screen view only.
United States Standard Photo Printing Sizes
If bringing in film or digital photos to a developer, you will notice that there are a range of different preconceived sizes of photo paper that you can have your photographs printed on. The size 4 inches by 6 inches is the U.S. standard photo print size for consumers. It is called "4R." This type of photo is the most common to put in photo albums and to give to friends and family in picture frames. However, there are a large range of different sizes for which you could easily print photos and buy frames. For example, 5 inches by 7 inches, which is the standard size "5R," and 8 inches by 10 inches, which is the standard size "8R," are the next most common photo sizes for frames and sharing. Generally, these standard size photos can be printed from a home computer or printer as well.
Some photographers who have high definition cameras may wish to print larger sizes of their work to make posters or large art prints. Many photo developers, including CVS, Walgreens, and Walmart Photo Center, allow the artist the option of printing posters of larger size, which need an oversized printer to do the size. These include the sizes 11 inches by 14 inches, 12 inches by 18 inches, 16 inches by 20 inches, or 20 inches by 30 inches.
Worldwide Standard Photo Printing Sizes
Many standard photo printing sizes are used worldwide, and these are called by the measurement of the photo in centimetres. Standard photo sizes throughout the world include the United States' most popular photo sizes: 4 inches by 6 inches, which is called "10 by 15 centimetres" globally, 5 inches by 7 inches, which is called "13 by 18 centimetres" globally, and 8 inches by 10 inches, which is called "20 by 25 centimetres" globally. Worldwide standard photo printing sizes make it easier to print, frame and share photographs with friends and family all over the world and to print and send pictures while travelling.
Digital Photo Print Sizes
With digital imagery has come the term "resolution," meaning how much detail, in dots, your photo has. DPI, or dots per inch, is the measurement of how many coloured dots are within a pixel. The more coloured dots there are, the more crisp your image will be. PPI, or pixels per inch, refers more to the size of the photo. Common display screens on computers are 72 by 72 PPI and DPI. To make a standard digital print, you will need about 300 DPI. That being said, a standard 4 inch by 6 inch photograph would commonly be 288 by 432 pixels. If you are planning to enlarge your photo or are planning to edit your photo in precise detail, you will need more DPI. For large prints or detailed editing, you will want to try 600 DPI. If you are printing a large poster, you will only need about 120 DPI. This is because the larger an image is, the less intricate it will be.
Digital Screen-Only Photo Sizes
Digital prints need many more pixels than images used online for websites. This is because common computer screens display images in 72 by 72 PPI and DPI. If you change the DPI on an image from 72 DPI to 300 DPI, you will generally not see the difference on the screen. However, when printing both images out, the 72 DPI image will be much less crisp than the 300 DPI image. Because of this, if you are preparing an image for screen-only viewing, you only need it to be 72 by 72 DPI. While your screen will recognise a change in pixels, it will not recognise an increase in dots.