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The Definitive Guide to Image Aspect Ratio for Printing

Created On: 3/21/2020

The Definitive Guide to Image Aspect Ratio for Printing

When you are taking your image and turning it into a poster (or canvas, decal, etc.), there are two aspect ratios that must be considered - the aspect ratio of the image and the aspect ratio of the print. Differences in these ratios can cause frustration, confusion, and ultimately leave you unhappy with your print. This guide will help you understand aspect ratios and the options you have when the image and print size don't perfectly match.

What is Image Aspect Ratio

Image aspect ratio is a fraction that describes the relationship between the height and width of your image. Like images, TV's have aspect ratios and they provide a good example to describe aspect ratio because there are only a few fixed sizes and almost everyone is familiar with them.

The classical TV aspect ratio is 4:3. Newer wide screen TVs have a ratio of 16:9.

Common TV Aspect Ratios

The actual width of a classical TV might be 40 inches wide and the actual height may be 30 inches high, but it will always be in that 4 width to 3 height ratio.

Your image has the same type of ratio, but the possible ratios are much more varied.

For example, this image has a width of 500 pixels and a height of 1000 pixels, so its aspect ratio is 1:2 or 1 to 2.

1:2 Aspect Ratio

This image has a width of 1000 and height of 1000, so its aspect ratio is 1:1 or 1 to 1.

1:1 Aspect Ratio

Aspect Ratio In Printing

Image Ratios Match

The best scenario when making a print is to have the image aspect ratio and print aspect ratio match exactly. If this is the case, you are golden. If the aspect ratios of the image and print are very close, you are also unlikely to have issues. You can usually crop a small section of the image in order to make the image fit the print size.

Image Ratios In The Ballpark

If the ratios of your image and print are similar but not exact matches, you will have three options: you can crop your image, you can add black or white bars to the image, or you can change your print size.

Cropping Your Image

Cropping your image means that you will place the image on the printing area where some part of the image is outside of the print area and will not be printed. The image below demonstrates how a crop works.

Example Cropped Image

Cropping the image works great for images that have large sections near the edges that are consistent and don't have key elements near the edges of the print area.

Adding Black or White Bars

If cropping your image doesn't work, the next option is to add black or white bars to the print space to fill in the missing space. Black bars are more popular, especially with landscape images, because they resemble wide format movie stills and are familiar to most people. The bars can also be added vertically but they don't look as natural. Below is an image of both a landscape and portrait image with black bars.

Example Image with Black Bars

We have an automatic solution for cropping or black bars on our customize tool. To get to the customize tool, you upload your image, select your size, and select “Customize” after you click continue.

Once in the customize tool, you’ll see some image control options for “Image Fit” and “image Fill.”

“Image Fit” will automatically place your image on the print area so that no part of the image is cropped and if black bars are needed, it will make sure the image is placed evenly in the middle.

“Image Fill” will automatically crop your image so that there are no black bars and the full print area contains your image. Parts of the sides or top and bottom will be cropped if the image doesn’t fit the print aspect ratio.

Image Fit and Image Fill

Changing Print Size

If cropping the image doesn't work, and adding black bars isn't what you want, the next option to consider is changing the print size to better match the image aspect ratio. You can use our aspect ratio tool to find a range of suitable sizes for your image.

Aspect Ratio Calculator

Changing the Image

If none of the above options works for you - the image crop won't work well, the black bars aren't acceptable, and you need the print to be a certain size because you have a frame or an exact amount of space it needs to fill, the final option is to email our customer service with your image attached and explain the issue you are having. We can try to fix it and if our fix doesn’t work, then moving to a different image may be the way to go. You can also consult our extensive guides on how to make a poster and how to make a canvas print.

Common Printing Aspect Ratios

2:3 Aspect Ratio

2:3 is the most popular aspect ratio for printing. Print sizes that are a 2:3 aspect ratio and are popular with poster, canvas, and decal printing are 24 x 36 inches and 40 x 60 inches.

3:4 Aspect Ratio

Some popular print sizes for the 3:4 ratio includes 30 x 40 inches and 18 x 24 inches.

4:5 Aspect Ratio

16 x 20 inches is the most popular print size for a 4:5 aspect ratio.


There are some other popular print aspect ratios like 8.5 x 11 inches and 11 x 17 inches.

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Holiday Shipping

Holiday Shipping Times & Cut Off We are currently able to ship all print types in time for the holidays, but the sooner you order, the better. Shipping companies are advising to ship packages for holiday delivery by December 16th. Many packages shipped after the 16th will still arrive in time for the holidays, but they are not guaranteeing it. While we do not have full control over the shipping and transit times, here is our best guess at the realistic cutoff dates. West Coast: Order by December 16th Central: Order By December 20th East Coast: Order by December 21st