So, my test was the following, how much of a difference does having four reasonable sized png images compare to four jpg images (uncompressed) and then compressed. Here are the results for you to see how much of an impact it makes.
PNG – Uncompressed:
PNG – Compressed:
JPG – Uncompressed:
JPG – Compressed:
So, what can you take away from this test?
That if you don’t have time to work with your file types it’s always worth compressing your images.
JPG is a more effecient file type for images (However there are situations where PNG is the only option, such as when you need a transparent background)
You can take away a reasonable chunk of page size by taking care of which images and compressing