When editing and saving files and choosing file extensions, you might have noticed the numerous options available when it comes to images. You’ll mostly see JPGs and PNGs, but what are they? And which one is the best to use?
What’s a JPG?
file formats that compress images through ‘Lossy Compression’. This means that the file is compressed into a smaller size – because it removes data from the image – at the cost of the image’s sharper quality. When you zoom in on a JPG, you’ll see a more pixelated image due to its compressed state, but because file sizes are smaller than PNGs, they are great file types for photos.
The data that is removed is basically a numbered list of the colours in the image, and a JPG file scans the image for colours that are similar enough to be given the same number. For example, lime and yellow-green might be close enough in colour that they can be labelled as 3 and 3 rather than 3 and 4.
And don’t worry about JPGs and JPEGs – they’re the same thing. Back in the earlier days of the Windows operating system, file format names were limited to three letters for file type acronyms (hence the missing ‘e’ in JPG). JPG/JPEG stands for ‘Joint Photographic Expert Group’, and is named for the committee that creates and oversees the standards for image compression and processing.
So what are PNG files?
PNG is an acronym for Portable Network Graphics, and these files have better quality because they use a Lossless compression method (though the files can end up being a lot larger compared to JPGs). The compressing works by detailing the image’s data through codes, and making a reference list/codebook that is stored within the file. The file then uses this reference list to reconstruct the image with each pixel correctly in place without any losses in the image’s quality.
This format is great for things like logos and designs, as they can retain quality without sacrificing detail in colours and sharpness. PNGs are also better when it comes to transparent backgrounds, which is necessary when working with images that need to be edited with a different background or other graphics.
Which is better?
Overall, it’s not too hard to pick the right file type, as it all comes down to what you need the images for:
If you plan on using images on a website, go with a JPG. Smaller files will reduce the loading time of the website, and they are better for detailed images because more can be presented without the need for an enormous file size. And if you want higher quality images that are needed for things like logos, icons, and other consistent branding (especially when it comes to printing), use PNGs.
You can remember the difference in when to use JPGs and PNGs with their names – JPGs are for photographic images (Joint Photographic Expert Group), while PNGs are for graphic images (Portable Network Graphics).
JPG are available in both CMYK and RGB colour modes, while PNG is only available in RGB. If you want to print your logo, use a high res JPG file to get the best print colour result. If you want to print with a transparent background, use PNG. If online file size matters use JPG.