JPEGmini

Get the smallest image file size without compromising quality or changing your workflow. You can upload Hi-Res photos faster, save tons of hard drive space, improve customer viewing experience and make your website faster.
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If you want to used high quality images in your website and there is an issue of space so dont worry JPEGmini is a solution you can compress size of high quality images but quality remain same it doesn't change.
If you try JPEGmini pro version it gives outstanding features like it allow to upload high-resolution photos from 128 MP camera and it done compression with high speed, you can setup different size for various images in one session and also allow to upload unlinited amount of photos.