My top three free image optimisation tools

I am often asked about image optimisation and compression and ‘how I get images so small’. Maybe many think the process is complicated or expensive, thinking that you need a certain paid-for tool like Photoshop or similar to edit images. I’m not sure.

The truth is, I often reach for three free online tools that do a really good job of it, quickly. I thought I would share those tools and simply how I use them. These aren’t affiliate links, just tools I use personally to help do a job.

Image optimisation phase one: Conversion

The first step I usually take is converting the image into a more suitable format. I see a lot of large PNGs out there, and I often take screenshots of websites that on a Mac, get generated as a PNG file. To enable a higher level of compression further down the line I will convert these PNGs into a JPG or WEBP. For this, I use Convertio. It is free, though has a premium version that allows for more concurrent conversions as well as the ability to convert larger files. I find that you can just use the free version if you only need to convert a handful of files per day.

Try Convertio

Image optimisation phase two: Resizing

It is important to resize your images so that they are no larger than their maximum displayed size. There is no need to load an image that is 1920px wide when it is only displayed at a maximum of 800px wide for example. It is also important to resize for responsive images, so you load the correct size for different device sizes and pixel densities.

To resize images I use PicResize. Again, it is free, but does have a paid version to remove ads and add in a couple of additional features like enlarging photos. PicResize can also do some image conversion, so I sometimes skip the first step and do two jobs on one tool. It is also reasonably good at the third step. Compression.

Try PicResize

Image optimisation phase three: Compression

The third step involves removing as much data from the image as possible without losing the visual clarity that people expect. Tiny png can help with this process. Free and super easy to use, you can compress up to 20 images at a time on the free version, but again, it has a paid-for version too. Tiny png does a great job of removing unnecessary data and meta from an image without compromising too much on the visual quality.

Try Tiny png

Image optimisation: Other options

These are just three tools to help with image optimisation. There are many others out there, free and paid for. There are also a host of tools, APIs and plugins for all manner of different website creation methods. I use WordPress a lot in my work, so there are a whole host of plugins that can help to do this process within the system. However, I always optimise images before I upload them, whether WordPress-based or not.


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