Image Compressor

Shrink JPG, PNG, WebP and AVIF files by quality or to a size budget — without uploading anything.

Runs on your deviceImagesWorkingNo account needed

What this tool does

Compression re-encodes an image at a quality level you choose. Most of what a camera or screenshot tool writes is detail the eye cannot resolve at normal viewing size, which is why a photo can often lose 70% of its bytes with no visible change.

The quality slider is not a percentage of visual fidelity — it is an encoder parameter, adjustable from 10 to 100. Around 80 is the point where most photographs stop looking different but keep shrinking; below about 60, edges and flat gradients start to show artefacts. Beginning at the default 78 and adjusting is more reliable than aiming for a target number.

The other mode aims at a maximum file size instead: give it a figure in KB or MB and the encoder quality is searched until the result fits. If quality alone cannot get under the budget, the dimensions are stepped down by a fifth at a time — up to eight attempts, and no smaller than 64 pixels on a side — unless you switch that off. When even the smallest attempt is still over, you get that file anyway plus a note saying by how much it missed.

How to use it

  1. Add your images. Any format the browser can decode, including JPG, PNG, WebP, AVIF and GIF. Several at once is fine; the settings apply to all of them and each is processed in turn.
  2. Pick a quality or a size budget. 78% suits photographs. Raise it for images with text or sharp edges, or switch to the size mode when an upload cap is the real constraint.
  3. Set the output format if you want one. Output can stay the same as the input or be forced to JPG, PNG, WebP or AVIF. A width or height cap can be applied at the same time, and transparent pixels are flattened onto a colour you pick when the output has no alpha channel.
  4. Compare and download. Before and after sizes, the final dimensions and the quality actually used are reported for each file, measured rather than estimated.

Processing & privacy

Runs on your device. Your file is processed directly in this browser.

Common use cases

Faster web pages

Images are usually the heaviest thing on a page, and the easiest to fix.

Email and upload limits

The size-budget mode exists for exactly this: fit a set of photos under an attachment cap without cropping or deleting any.

Freeing up storage

A folder of holiday photos often halves with no visible difference.

Marketplace listings

Many platforms reject images over a few megabytes, or degrade them badly themselves.

Questions

Are my photos uploaded?
No. Compression happens in this browser tab using the canvas encoder. Photos are personal, and there is no reason for them to travel to a server for this.
Why did my file get no smaller?
Some images are already near optimal — screenshots, simple graphics, or files a phone already compressed. When you are compressing by quality, keeping the same output format and not capping the dimensions, the tool compares the two and hands back the untouched original if re-encoding grew it. That safeguard is a checkbox you can turn off, and it does not apply once you change the format, cap the size or switch to the size-budget mode, so those paths can genuinely return a bigger file.
Does compressing lose quality?
JPG, WebP and AVIF are lossy, so some data is discarded. At quality 78 that is usually invisible on photographs. Repeatedly compressing the same file compounds the loss, so always start from the original.
Will it strip my EXIF data?
Yes. Re-encoding through the canvas drops camera and location metadata as a side effect, and there is no option to preserve it. If you want to keep it, this is not the tool; if removing it is the goal, Remove EXIF does it without touching pixels.
What about PNG?
PNG output is lossless, so the quality slider is ignored for it entirely — there is no palette reduction or lossless re-packing here, and a canvas-written PNG is frequently larger than the file you started with. For a PNG the only real savings come from capping the dimensions or choosing WebP, AVIF or JPG as the output. The size-budget mode refuses PNG outright and asks you to pick a lossy format.
Will it reduce photo size without visible loss?
Usually, yes. At the default 78% quality most photographs are visually indistinguishable from the original at normal viewing size, while the file is a fraction of the size. Lower the quality only until you can see the difference, then step back one notch.

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