Skip to main content
zerouploads

compress JPG

You choose the quality, and you see both sizes.

82% is where most photographs stop looking any better. Text and flat colour want more.

The converted file appears here, with its size before and after, ready to save.

The short answer

Compressing a JPEG means saving it again at a lower quality, and every save throws a little more away. This page puts the setting in front of you and shows the size before and after, so the trade is a decision rather than a surprise.

Compressing a JPEG means saving it again at a lower quality. This puts the setting in front of you rather than picking one silently, and shows the size before and after so the trade is a decision.

The formula

decode the JPEG → draw it onto a canvas → encode again at the quality you choose

Worked examples

Quality 95%
barely smaller than the original
Quality 82%
much smaller, no visible loss on a photo
Quality 60%
small, with blocking visible in flat skies

Reference table

What each quality setting is good for
QualityUse it forWhat to watch
95%Archive copies, printHardly smaller than the original
82%Photographs on a web pageNothing, on most photographs
70%Thumbnails, background imagesFlat areas start to band
60% or lessWhen the size is all that mattersVisible blocking and soft edges

How to use it

  1. 01Drop the JPEG inOr pick a file. It is decoded by your own browser; nothing is uploaded.
  2. 02Move the sliderStart at 82% and go down until the size is acceptable or the picture is not.
  3. 03Save the resultThe panel shows how much smaller it got, so you can judge whether it was worth it.

Also searched for

Searches that land here include compress jpg, compress jpeg, reduce jpeg file size, jpeg compressor and make image smaller.

What compressing a JPEG actually does

It re-encodes, it does not tidy up

There is no spare space in a JPEG to reclaim. The only lever is how much detail the encoder keeps, and lowering it means permanently discarding some. That is why the honest description is "save again at a lower quality" rather than the "optimise" most tools advertise.

Where the visible line sits

On a photograph, 90% and above is nearly indistinguishable from the original and barely smaller. Around 82% is the point most people cannot see a difference on a normal screen. By 70% flat areas like skies start to band, and at 60% and below the eight-by-eight blocks the format works in become visible in shadows.

Pictures that are not photographs

Screenshots, diagrams, logos and anything with text do badly at any JPEG setting, because the format is built to blur exactly the sharp edges those images are made of. Those want PNG for exactness or WebP for size.

Questions people ask

How much smaller will my file get?

It depends on what the original was saved at, which is why this page shows you rather than promising a number. A photograph straight from a phone at maximum quality can often lose half its size with nothing visible. One that has already been squeezed by a messaging app may barely shrink at all, because the detail is already gone.

Is it bad to compress a JPEG more than once?

Yes, and it accumulates. Each save discards detail permanently, so a file that has been through several rounds shows blocking and colour smearing that no amount of quality on the next save can repair. Work from the largest original you have rather than the copy someone sent you.

Why is there no target file size?

Because hitting an exact size means encoding repeatedly and guessing between attempts, and the result is a quality setting you did not choose. Moving the slider and watching the number is the same process with you making the decision.