Why it was Top: 2021 was the year Caesium reached full maturity. It was the only free, cross-platform tool that could compete with paid software.

With rising privacy awareness, 2021 saw a spike in tools that strip EXIF and GPS data from JPEGs before uploading. The top 4 were:

If you are looking for a tool that replicates the "4jpg top 2021" experience today, ask yourself these three questions:

1. Do you need speed or quality?

2. Are you using Windows, Mac, or Linux?

3. Is your source image already optimized? Most "Top" tools of 2021 failed on images that had been saved 20 times. Use IrfanView (another 2021 honorable mention) to "clean" the JPEG first.

Why it was top in 2021: Mozilla released MozJPEG v4.0, the best encoder for traditional .jpg files. It used trellis quantization and progressive scan optimization to reduce file sizes by 15-20% compared to standard libjpeg.