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Compress Image

To shrink a JPG, PNG or WebP image, drag the quality slider or set a target file size such as 100 KB, then check the result before you download. At quality 80, photos typically lose 50–80% of their size with no visible change, and resizing saves far more. Images are processed in your browser and never uploaded.

Files never leave your device

Updated

How to use Compress Image

  1. 1Add one or more images.
  2. 2Drag the quality slider, or choose Target file size and enter a limit such as 100 KB.
  3. 3Compare the original and compressed previews side by side.
  4. 4Download the images individually, or all of them as a ZIP.

How it works

Each image is decoded, drawn onto a canvas, and re-encoded at the quality you choose. Lossy encoders such as JPEG and WebP discard the detail human vision is least sensitive to — mostly fine colour variation — which is why an image can lose 70% of its file size while looking essentially unchanged.

Quality between 75 and 85 is the practical sweet spot for photographs. Below about 60, JPEG artefacts start appearing around hard edges and in flat areas of colour. Screenshots and graphics with sharp lines behave differently: they compress badly as JPEG and are better left as PNG or converted to WebP.

Optionally the image can be resized at the same time, which usually saves far more than quality alone. A 4000-pixel photo displayed at 1200 pixels wide is carrying more than ten times the data it needs.

In target-size mode the tool searches for the highest quality, between 40% and 92%, that keeps each file under your limit, re-encoding several times to find it. If even 40% is too large, the image is scaled down in steps — file size falls roughly with pixel count — and searched again, so a 100 KB limit is met with a sharp, smaller picture rather than a blocky full-size one.

Images are decoded by the browser, redrawn on a canvas and re-encoded on your own machine. Nothing is uploaded, so there is no waiting on a queue and no copy of your photos anywhere else.

Tips and common mistakes

  • Resize before you compress. A photo shown 1,200 pixels wide does not need to be 4,000 pixels wide, and cutting the pixel count saves far more than lowering quality.
  • Start at quality 80 for photographs and move in steps of five. Below about 60, blocks and halos start to show around edges and in smooth areas like sky.
  • Judge the result zoomed in, not as a thumbnail. Look at hair, text and the edges of objects against plain backgrounds.
  • Keep your originals and always compress from them. Compressing an already compressed copy adds more damage each time.

Frequently asked questions

How do I compress an image to 100 KB?
Choose JPG or WebP, switch Compress by to Target file size and enter 100, or tap the 100 KB preset. Each image gets the highest quality that fits; if even 40% quality is too large it is scaled down until it fits, and you are told if a limit cannot be reached.
How much smaller will my image get?
Typically 50–80% for photographs at quality 80. The exact figure depends on the image — a detailed landscape compresses less than a portrait with a smooth background. The tool shows the real saving before you download.
Will compression ruin the quality?
At quality 80 the difference is very hard to see at normal viewing sizes. The before-and-after preview lets you judge for yourself at full zoom.
Can I compress PNG images?
PNG is lossless, so quality settings do not apply. The most effective way to shrink a PNG is to resize it, or convert it to WebP, both of which this tool can do.
Is there a file size limit?
Images up to 50 MB each are accepted. Very large images use a lot of memory during processing, so on a phone you may want to work through them in smaller batches.
What quality should I use for images on a website?
Between 75 and 85 for photographs, at the width the image will actually be shown. Screenshots and graphics with text look better as PNG or WebP.
Does compressing remove a photo's location data?
Re-encoding in the browser does not carry camera metadata across. If removing location is the main goal, check the result with the EXIF Viewer and Remover.
Can I compress many images at once?
Yes. Add a batch, compress them together and download them as a ZIP.
Why did my image get bigger after compressing it?
That happens when the original was already compressed at a lower quality, or when a photo is kept as PNG. Start from the original file, lower the quality or the pixel size, and keep the original if the result is not smaller.
Why do two photos with the same pixel size compress to such different sizes?
File size depends on detail as well as pixels. Sky and plain walls compress well; foliage, small text and noise from low light do not. Setting a target size such as 200 KB lets the tool find a suitable quality for each photo.
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