♥ Price
JPEGmini is $59,
Unbelievable Image Optimizer is only $8.97 when crazy promotion.
♥ Compression ratio
JPEGmini is 4.3x,
Unbelievable Image Optimizer is 7x.
Details of the test.
♥ Feature:
JPEGmini: Only jpg and heic can be compressed.
Unbelievable Image Optimizer: can compress jpg, jpeg, png, gif, pcx, bmp and supports transparent png.
Unbelievable Image Optimizer can output jpeg2000, which can provide higher compression than jpg.
2. Compression ratio comparisons
Image optimizer ORIGINAL size optimized size compression
Unbelievable Image Optimizer 624 KB 89 KB 7.0x
kraken.io 624 KB 252 KB 2.5x
JPEGmini 624 KB 144 KB 4.3x
TinyPNG,TinyJPG 624 KB 149 KB 4.2x
optimizer size compression
Unbelievable 89 KB 7.0x
kraken.io 252 KB 2.5x
JPEGmini 144 KB 4.3x
TinyPNG 149 KB 4.2x
3. Compression speed
Because only Unbelievable Image Optimizer and JPEGmini are local batch compression, the others are online compression, Unbelievable Image Optimizer and JPEGmini are very fast, and the other speeds are obviously slow.
Unbelievable Image Optimizer is the only batch processing, high-compression, high-speed, reliable, cheap software.
disadvantages of Most image optimizers

Troublesome
Many times uploading and downloading images is very troublesome.

Very Slow
Both Uploading and Downloading are slow.

No Image privacy
Images Are Sent To Website‘s Server, You Know It. Not Real Guarantee.
uncommon advantages of unbelievable image optimizer

Convenient
Compress images in a directory at a time. No uploading or downloading images.

Very Fast
Compress locally, and native software is much faster than website.

Safeguard privacy
Images are compressed on your computer and are not sent to website.
New 3.0 released, support png, Gif, Pcx, Bmp and Jpeg2000
Crazy New Year promotion: double discount 25% + 69%, if you find the discount code. 100 discount product.
2020.2.1-2.3