There are so many types of Image files that are available. You might have wondered which one is best for Image SEO and why there are so many?
I mean, why not all of them are JPEG or PNG? What makes them different?
This post will see the eight most used image file extensions and learn what makes them unique.
- JPEG (or JPG)
- PNG – Portable Network Graphics (.png)
- GIF – Graphics Interchange Format (.gif)
- WebP (.webp)
- TIFF – Tagged Image File (.tiff)
- PSD – Photoshop Document (.psd)
- AI – Adobe Illustrator Document (.ai)
- RAW – Raw Image Formats
But before moving, let’s understand some terms:
Vector Images: Mathematical equations help in designing the vector graphics. The equations are translated into various curves, lines, shapes, and figures. Vector images do not get blurred if you zoom them, and they are responsive. That’s why elements and logos are in vector image format. E.g., SVG and AI
Raster Images: Raster images are pixelated image file types. Made of various pixels, Raster images are not responsive. They get blurry as we enlarge the size of raster images. Most of the images we see on the Internet and daily life are raster images. E.g., Gif, Jpeg, Png
Lossless compression: Lossless compression means no data has been lost during the compression of the image. You can reduce the size of the file without losing the image data. It is done by deleting the image meta-data. Png and Gif are Lossless.
Lossy Compression: In Lossy compression, you lost some of the data (pixels) from the image permanently. You cannot revert and have the original pic back. E.g., Jpegs, Pngs
Image meta-data: The information about the image is usually hidden inside the image. We call it meta-data. Information such as camera, time, location, author, etc. can be viewed with tools. You can use Metapicz to view the data.
#1 JPEG (or JPG) – Joint Photographic Experts Group (.jpg)
JPEGs are the most commonly used image file type on the web. This image format keeps the lossy and compressed image data and reduces the file size significantly. However, JPEG maintains the quality and clarity of the image.
This reduction without losing quality is why JPEG is a preferable image format to use on the Internet. It is easy and quick to share JPEG via the web. You can store lots of JPEG in a low storage device, as JPEG does not have a large file size.
You can also have high-quality heavy images with JPEG. JPEG has in-depth color grading, which provides a psychological sense to the picture.
When to use: For the web, and when the image does not have text.
#2 PNG – Portable Network Graphics (.png)
PNG is another popular image file format that we see on the Internet. Lossless means you can edit an image without the image losing its quality. PNGs are lossless formats of images.
PNG’s main property is to have the image on a transparent background, and that’s why we often see PNG format is used for logos, lines, symbols, etc.… The PNG images are sharper than the JPEGs and a better choice for text-based images.
When to use: If the image has text, lines, and shapes, use PNG for the sharper picture.
#3 GIF – Graphics Interchange Format (.gif)
Gifs are lossless too, but it can’t be reduced as much as the Jpeg. Never used for printing, but GIFs are the most popular format when it comes to animated images.
Moreover, GIFs have limitations for the colors. From the set of 16 Million colors, Gif can only render 256 colors. If the image has more than 256 colors, it will lose a lot and will not be lossless. However, under 256 colors, Gif remains lossless.
When to use: Short animation that does not have many colors in it.
#4 WebP (.webp)
Made especially for the web, WebP is a modern image format that offers lossless and lossy image compression. Create and developed by Google, WebP focuses on making the image light to load as quickly as possible.
This file format is nearly 25% smaller in size than the PNG and JPEG. To convert the images into WebP on WordPress, you have to download a plugin.
When to use: WebP is excellent to use on websites or blogs.
#5 TIFF – Tagged Image File (.tiff)
TIFF formats are large types of Image files. They have so much information filled in them that they usually are of heavy sizes. They are uncompressed and can be used as a lossless or lossy image.
TIFF is also a highly flexible format, and it retains all the data after editing. When working on photo editing software (Photoshop, Adobe, Snapseed), the TIFF format is preferable because of its stores’ image data.
You should never use TIFF for the web, as it will take forever to load, and it is crucial that your site load under 3 seconds.
When to use: To get something to print in a big size or keep the image data.
#6 PSD – Photoshop Document (.psd)
PSD is created by Adobe’s Photoshop Application — popular editing software. The format it makes is image editing friendly and supports multiple layers of image and options.
PSD stores high-quality graphics that store all the data related to the image. A PSD file can hold up to 30,000 pixels in both height and width. The size of the image file can be extended to 2 GB.
Graphic designers and professional image creators use PSD format to make templates and graphics. You should not use PSD files for the websites unless you have a site where you sell PSD templates.
When to use: For high-quality printables and editable graphics.
#7 AI – Adobe Illustrator Document (.ai)
AI is another image format created by Adobe. AI files are vector graphics, all on a single page. The best property of an AI file is to retain the image’s details even at the maximum zoom.
AI format is widely prevalent among graphic designers, as AI types of Image files can be used for various prospects, from the web to printables.
When to use: Designers use this format when creating something from scratch. The file is easy to share among the designers for editing.
#8 RAW – Raw Image Formats
When you first click the image, it is in Raw format. The least processed image type is RAW image files—basically, the first format when the image is created.
Digital cameras use RAW image types, and they store lots of information in the picture. RAW format captures and holds all the elements of the photo.
Most of the time, the pic has to be converted into TIFF with software. To use on the web, one has to convert the image into JPEG. It is also advisable not to keep your files in RAW formats. There is no single RAW format, and it depends on the camera company. They update the program with each new model, and the RAW file you have today becomes inaccessible in twenty-thirty years.
When to use: Not for the web, but you can keep RAW files and retain the image data.
Images are essential for making the page interactive, but so is the site’s fast loading speed. You have to find the right balance between quality and the size of the image.
To use the image for better SEO performance, check our Image SEO tips.
I hope this article answered your question regarding types of image files. If you have more doubts, leave them in the comment section.