Recently we were tasked to compress all the PNGs on the Inchcape project, so we were looking around for tools that could take all the PNGs and automatically go through each one and compress them. I found and tested three PNG compression tools – these are PNGGauntlet, PNGoo and an online web-based PNG compressor called Tiny PNG.
To make the test accurate, we took a folder containing a test PNG image, and compared PNG compression and ease of use for each.
PNGoo
Starting off with PNGoo, it’s relatively simple to use. You go into each folder of your images folder, drag the .png files in that folder and click the ‘Go!’ button! If you are a little afraid or just want to experiment and compare with your original images, you can set an option which allows you to output to a directory of your choice.
On Inchcape, it delivered 10-15% compression on file sizes and with a little more experimentation, it can be 20%. Whilst it isn’t designed to replace server side image compression tools like Grunt, it’s a very quick and easy tool if you need to compress images quickly.
Below is an example of a test PNG asset and on that asset, you can see PNGoo managed to reduce the size of the PNG. You can see that it went down from 35k to 12k, a third of its original size!
PNGGauntlet
PNGGauntlet has an almost identical interface and works very much the same way as PNGoo. Again, we tested PNGoo with the same file to compare the results
As you can see from the screenshot, the compression the tool achieved wasn’t as high as that of PNGoo.
TinyPNG
TinyPNG (https://tinypng.com) is an online picture compression tool and allows you to compress up to 20 images at a time. It’s a very nice tool to use – simply drag the images that you want to compress and let TinyPNG do the job. With my test file, it was comparable to PNGoo and compressed the original file by 71%.
As you can see, TinyPNG is very useful in that it’s an online tool and you don’t need to install any additional software. The only downside is that if you have more than 20 images in a folder, you would have to do 20 at a time.
Summary
After comparing the three tools, we found the most effective tool in terms of ease of use and the amount of files it can compress at any one time is PNGoo. It’s also lightweight and won’t take up too much space on your hard drive.
