Question 1

What's the difference between the percentage modes and Custom Target?

Accepted Answer

Light, Medium, and Strong each guarantee a specific percentage reduction (10%, 25%, 50% smaller) rather than a vague quality label. Custom Target instead lets you set an exact file size limit, useful when you have a specific size requirement (like a 2MB upload cap) rather than a general "make it smaller" goal.

Question 2

Will converting a PNG to JPG first help compress it further?

Accepted Answer

Often yes, if you don't need transparency -- JPG images generally compress much further than PNGs before quality loss becomes noticeable, so converting first can get you a meaningfully smaller final file.

Question 3

Does compressing actually reduce quality, or is it lossless?

Accepted Answer

Honestly, it's lossy -- Light, Medium, and Strong achieve their guaranteed size reduction by re-encoding the image at a lower quality setting, which does mean some real, if often visually subtle, quality loss. "Without losing quality" isn't an accurate way to describe any of these modes; the goal is keeping the result looking as close to the original as possible at the target size, not zero quality change.

Question 4

Will my transparent PNG or WebP stay transparent after compressing?

Accepted Answer

No -- the compressed output is always a JPG regardless of what format you uploaded, and JPG doesn't support transparency. Any transparent areas get filled in rather than staying transparent. If you need to keep transparency, this isn't the right tool for that specific image.

Question 5

Are my images uploaded to a server?

Accepted Answer

No -- compression runs entirely in your browser, including the guaranteed-reduction target search. Your image never leaves your device at any point.

Question 6

What does Manual Quality mode do differently from the percentage presets?

Accepted Answer

It gives you direct control over the compression quality slider yourself, rather than a guaranteed percentage reduction -- useful if you want to visually judge the quality-vs-size tradeoff yourself instead of trusting a fixed target.

Question 7

What happens if my Custom Target is smaller than the image can realistically reach?

Accepted Answer

The tool searches down to the lowest reasonable quality setting and returns the smallest result it can produce -- if that's still larger than your target, you'll see the actual result size rather than a silently wrong or failed compression.

Question 8

Can I compress multiple images at once?

Accepted Answer

Not here -- this handles one image at a time. For compressing several images together in one pass, Bulk Image Processor handles a batch instead.

Compress Image

What is this tool?

How to use it

Watch: Compress Image in Action

Frequently asked questions