Question 1

How much smaller will my image get?

Accepted Answer

For a photograph, usually between half and four fifths smaller with nothing visible lost — most of a JPEG is detail your eye was not resolving. For a logo, a screenshot or a diagram stored as PNG the answer is much lower, typically ten to thirty per cent, because nothing is discarded at all and the saving is only what a better encoder can find. An image that has already been optimised may not shrink at all, and you will be told that rather than handed a file that grew.

Question 2

Does compressing lose quality?

Accepted Answer

For JPEG, WebP, AVIF and JPEG XL, yes by design — that is what the quality slider controls, and at the default of 75 the difference is very hard to see at normal viewing size. For PNG it is lossless: every pixel survives exactly, and the file gets smaller only because the encoder tried harder. The two are genuinely different operations and this page does not pretend otherwise.

Question 3

Can I compress an image to an exact file size?

Accepted Answer

To a size at or under a limit, yes, which is what an upload form with a cap actually requires. Pick the target and the compressor encodes at several qualities, narrowing in on the highest one that still fits underneath. If your number cannot be reached without wrecking the picture it says so instead of quietly handing you something unusable.

Question 4

Should I compress or convert my image?

Accepted Answer

If the format is already right for the content, compress. If it is not, converting will save far more in one step: a photograph stored as PNG is often ten times the size of the same picture as a JPEG or WebP, and no amount of lossless optimisation closes that gap. The pages here say so where it applies rather than selling you the tool you happen to be standing in front of.

Question 5

Is resizing better than lowering the quality?

Accepted Answer

Usually, and it is the most overlooked setting on this page. A photograph 4000 pixels wide that will be viewed in an 800-pixel column is carrying about four fifths of its bytes for nothing, and dropping the dimensions costs you nothing visible at the size it will actually be seen. Every page here offers a width limit alongside the quality control for that reason.

Question 6

Are my images uploaded anywhere?

Accepted Answer

No. Every compression on this site runs in your browser — the image is decoded, re-encoded and handed back without leaving your device. You can verify it by watching the network tab in your browser's developer tools, or by disconnecting from the internet and compressing anyway.

Question 7

Can I compress several images at once?

Accepted Answer

Not yet. Batch handling currently covers conversion — drop a folder of files, pick one target format and take a single ZIP back — but compression is still one file at a time, because a quality setting that suits one photograph rarely suits the next. A shared batch setting is on the list.

Question 8

Does compressing remove EXIF and location data?

Accepted Answer

Do not rely on it. Compressing a JPEG or WebP re-encodes it from pixels, which as a side effect leaves the original EXIF behind — but PNG optimisation works on the existing file and can preserve its metadata chunks. If removing the data is what you actually want, use the metadata remover, which is built for it, tells you what was in the file, and confirms what it took out.

Question 9

Is there a size limit, and does it cost anything?

Accepted Answer

No limit we impose and no cost. Because nothing is uploaded there is no server capacity to ration, so there is no daily cap, no queue and no account. The practical ceiling is your own memory: a very large image on a phone is the first thing to struggle.

Question 10

Which formats can be compressed here?

Accepted Answer

PDF, JPEG, PNG, WebP, AVIF and JPEG XL. PDF works differently from the rest and has three modes, because a document can be mostly text, mostly photographs or a scan, and those shrink in completely different ways. Among the image formats, AVIF and JPEG XL are the two worth knowing about if you control what your visitors receive — both routinely beat JPEG substantially at the same visual quality, with AVIF supported by every current browser.

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