Image File Types: Everything You Need To Know

What is image compression?

Image compression is the process of reducing the size of an image in order to improve file-sharing, downloading, and/or viewing speeds, especially when attempting to load an image online. Compressed images may have lossless or loss characteristics, depending on the type of image file that is used and the format the image is saved in.

Lossy compression

A lossy compression is the compression of an image that may reduce the overall quality of an image in exchange for a smaller file size output. While lossy compressions typically result in smaller file sizes, they will require the sacrifice of a perfectly rendered image.

Lossless compression

Lossless compression can help to reduce a file's overall size without losing any of the file's original details. It is important to note that a lossless compression will not reduce your image file size as much as lossy compression.

High resolution vs low resolution

With any image file, there are both high-resolution and low-resolution options that can be used for a variety of applications, both online and off. When you are working with high-definition images online or off, you may hear the term DPI. DPI stands for Dots Per Inch, which is a metric used to measure the overall size and quality of a digital image (for print or online purposes).

A DPI of 300 or greater is typical for print jobs, but is extremely large and overbearing for standard web images, which typically have a DPI of 72. High-resolution image file types require 300 DPI or greater. Image file formats with less than 300 DPI are typically considered low-resolution or web images.

Raster image formats

Raster image formats are the most common types of image file types you will find on the web today. Raster images are images and photos that have been generated with the use of individual pixels. As pixels stretch and are enlarged at a lower resolution, they become blurry and distorted.

Raster image files are the most common type of image found online today, whether you are looking at standard photos or animated graphics. Raster files must also be saved in the exact dimensions that a user wishes to display or print.

GIF

A GIF, or a Graphics Interchange Format file, is typically a file type reserved for web graphics as well as animated graphics. All animated graphics found online are GIFs, but not all GIFs are animated. A GIF file is ideal for images and graphics that include multiple layers or even sections in the image that are to be rendered entirely transparent. A GIF file can display up to 256 colors, which can limit how a GIF or an animated graphic is rendered, especially when attempting to render a highly-detailed image.

PNG

A PNG, or a Portable Network Graphics file, is often known as one of the highest-quality raster image file formats available. The PNG was originally developed to help replace the GIF format, although the GIF format is still one of the most popular raiser image file types available today. With a PNG file, it is possible for an image to handle up to 16 million colors in total, providing users with complete and total control over how high-quality each image they compress is once the process is complete.

JPEG

The JPEG, sometimes referred to as the JPG, is one of the most popular image formats in the world. JPEG, also known as Joint Photographic Experts Groups, is one of the most standard picture file types. All JPEG images are considered "lossy", or they have the ability to be reduced in quality when compressed in order to simultaneously reduce the file's overall size.

JPEG images are commonly rendered when taking photos with standard cameras or even with the use of smartphone cameras. JPEGs are also common among those who work in graphic programs such as Adobe Photoshop. The use of the JPEG image is best for web graphics, images for Ads, emailing photos, and even hosting or creating your own PowerPoint presentation.

TIFF

A TIFF, or a Tagged Image File Format, are image files that do not require image compression in order to save lossless images. TIFF files are typically considered high-quality and high-resolution raster images, which often result in larger file sizes than alternative image file formats such as GIF and JPEG file types.

RAW

RAW image files are image files that have been generated by both scanners as well as digital cameras. These images are typically considered unprocessed and can be classified as a "digital negative" in many instances. RAW image files contain many details and additional information about the image itself, which can be processed in various editors for future use.

Typically, RAW images are rendered as much larger than compressed images, as they are taken and captured in their original form. If you want to reduce the size of a RAW image, you will first need to process the image using your preferred image editor. You will then need to save and export the image using the file type of your choice.

PSD

A PSD, or a Photoshop Document, are image files that are native to Adobe Photoshop. These file types can include items such as digital layers, vector items, as well as different sections of typography. PSD image file types can be accessed and edited at any time without losing the ability to move or relate objects with just a few clicks. PSD files are ideal formats for ongoing projects as well as for any graphics that may be edited and updated in the future.

Vector image formats

Vector image file formats differ from raster images as they are not as restricted or limited as raster files. Rather than generating images with the use of individual pixels, vector image file formats use built-in algorithms that remain proportional as users resize and edit the objects in real-time. Some of the most well-known vector file types include AI, PDF, and EPS files, which are typically used in various areas of graphic design.

PDF

A PDF file, or a Portable Document Format file type, is a file type that was originally designed to share rich information on just about any platform and from any remote location with a working internet connection. PDF files are typically generated and opened using Adobe Acrobat, one of the world's leading PDF file creators and viewers.

A PDF file is ideal for sharing vector renders with those who do not have graphic design or editing software themselves. Using PDF files is also commonplace when creating forms, contracts, and relevant business paperwork.

AI

An AI image file, or an Adobe Illustrator image format, is one of the most popular image formats used and preferred by illustrators and graphic designers alike. An AI file is designed for Adobe Illustrator designers, but it is also compatible with the entire Adobe Suite, including Adobe Photoshop, Adobe InDesign, as well as Adobe Acrobat.

The use of AI files is essential for those who prefer to create artwork from scratch without the risk of losing the quality of the image or graphic itself. With an AI file, generate vectors using built-in algorithms and say goodbye to lossy compression that comes standard with traditional JPEG and GIF images.

SVG

An SVG image file is an older image file, but it is classified as a vector image file, as it does not create a loss of quality or compression when saved as a smaller file size. An SVG file is a Scalable Vector Graphic, or a graphic that can be freely edited, scaled, and enlarged without the risk of losing the look, shape, or quality of the original image. SVG files are not as popular as AI or PSD files, but they are ideal for quick diagrams, generating icons, and even working on simple visual presentations without losing quality.

EPS

EPS picture file types are also universally loved and adored by those who typically work with vector or high-resolution graphics. EPS image file types, or Encapsulated Postscript image file forms, are designed for those working with high-resolution vectors and graphics across multiple platforms and software programs.

Rather than being limited to using AI and PDF or PSD files with the Adobe Suite, the EPS file type is more flexible and universal, as it can be opened in most programs that support standard vector image file types today. Saving a file as an EPS vector ensures that it is possible to also load the file in alternative programs other than Adobe, such as Quark or Corel Draw.

Image file size is important, too!

Whenever you are using an image to convey a message or to appeal to a prospective customer, you will need to choose image formats that are not only appropriate but compatible with where you upload or place the image. It is not only important to keep the image formats you use in mind, but also the file size of each image you intend to upload, share, or implement in your next marketing campaign.

You may also want to consider whether you will need to add alt text to any of the graphics you intend to use in a campaign before settling on an image format that is appropriate for your needs. Image file size can play a major role in how individuals respond to an advertisement or promotion you share. If a user is unable to load an image or graphic immediately, they are much more likely to look for another source for the images or information they are seeking.

Whether you're creating a brand new marketing campaign or looking to implement image content blocks in your email newsletter, Mailchimp has everything you need to get started.

With Mailchimp, discover how to add properly sized images for your website and newsletters, and even receive image recommendations for the marketing funnels you create for your business.