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Image Compressor

Shrink JPG, PNG and WebP files in your browser. Compare before and after, aim for a file size, and download the whole batch.

  • Preview
  • Unlimited
  • No signup
  • Private
  • Works offline

Image compression workbench

No images yetdrop, paste or choose files to start

Choose image files

Preview

Add images to see them before and after

Before
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After
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Compression

Compression method

You pick the look. The size follows. Try 70 to 80 for photos.

Output options

Limits the longer side. Big photos shrink. Small ones stay as they are. This saves more than quality does.

Writes JPG for every file.

EXIF and GPS are always dropped. Output is always tagged sRGB.

Add images to start

How it works

  1. 01

    Add your images

    Drop, paste or pick any number of files. They stay in this tab and are never sent anywhere.

  2. 02

    Pick a quality or a size

    Move the slider, or type the file size you need and let the encoder find the quality.

  3. 03

    Compare, then download

    Drag the divider to see before and after. Scroll to zoom in. Save one file, or the batch as a zip.

Quality, target size and lossless

Quality gives the encoder a level to aim for, not a file size. Lower values throw away more detail and make smaller files. Photographs take this well. Text, line art and screenshots show it first, so check those at 100% before you save.

Target size works the other way round. You give the size, and the tool encodes the file six times to find the highest quality that fits. Each try halves the range it still has to search. Format overhead means the last few kB are not always reachable, so the result sits at or under your number rather than exactly on it.

Lossless keeps every pixel and still often shrinks the file, because most images are stored less tightly than they could be. It suits screenshots, logos and anything that has to stay exact. It can also come out larger than a source that was already squeezed hard, and the queue tells you when that happens.

Formats
JPG, PNG and WebP out. Any image your browser reads goes in.
Batch
No limit on files. One at a time, so memory stays flat.
Target size
Six tries at the quality that fits the size you asked for.
Originals
Never touched. Compressing always writes a new file.

Frequently asked questions

Will compressing spoil my photos?
At quality 70 to 80 most photos look the same at normal viewing size. Drag the divider, then scroll to zoom in on the detail you care about. Text and line art show wear soonest, so give those a closer look.
How do I compress an image to an exact file size?
Choose Target size and type the size in kB. The tool encodes the file six times, halving the quality range each try, and keeps the best one that fits. Format overhead means the last few kB are not always reachable, so the result is at or under your number.
How many images can I compress at once?
As many as you like. Files run one at a time, so a long queue never holds a stack of decoded images in memory. Your free memory is the only real ceiling.
Do my images get uploaded?
No. Every decode, comparison and re-encode happens in this tab. The image data never leaves your device, so there is no copy to delete.
Which format should I choose?
JPG is the default. It opens anywhere and the quality slider works on it, but it has no transparency. WebP goes smaller still at the same quality and keeps clear areas clear. Keep original leaves the format alone. Avoid PNG here: it has no lossy mode, so quality does nothing and the file usually grows.
What does the Lossless setting do?
It keeps every pixel exactly as it was and still often shrinks the file. Output is WebP, or PNG if you pick it. JPG has no lossless mode, so a JPG choice switches to WebP rather than quietly losing detail.
Why did my file get bigger?
Two reasons. PNG output cannot be made lossy, so quality does nothing and the encoder often writes more bytes than it read. Or your source was already squeezed harder than the setting you picked. Choose JPG or WebP, or lower the quality. The queue shows the new size on every row before you save.
Can I compress a PNG?
Yes, but not to a PNG. PNG stores every pixel exactly, so there is no detail to trade for size and re-saving one usually makes it larger. Leave the format on JPG or WebP and a PNG photo often loses most of its size with no visible change. Pick Lossless if it has to stay exact.
Does it remove EXIF and GPS data?
Yes, always. The browser redraws the pixels onto a canvas and nothing else comes along, so camera settings and location are dropped. The output is tagged sRGB. Neither is a setting here.
Can I make the pixel size smaller too?
Yes. Set a longest edge and a big photo is scaled down before it is encoded, which saves far more than quality alone. A smaller image is left alone. For an exact width and height, use the image resizer.
Are the original files changed?
No. Your browser reads each original and writes a separate new file for you to download. The file on your disk is untouched.
Does this work offline?
Yes. Once the page has loaded, compressing carries on with no network connection.

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