ZapKit

Image Compressor

Make photos and screenshots smaller for email, forms and websites. Set a quality or a target size in KB; every image is compressed on your device and never uploaded.

What is an image compressor?

An image compressor makes an image file smaller, usually by lowering its JPG or WebP quality, reducing its pixel dimensions, or both. Smaller files upload faster, fit within the size limits of job portals, exam forms and email, and make web pages load quicker.

This compressor works on batches: drop in a folder's worth of photos, choose one setting, and every file is redone live as you move the slider. It can also aim for a size such as 50 KB or 200 KB, picking the highest quality that fits so the result looks as good as the limit allows. Files never leave your browser.

How to use the Image Compressor

  1. 1.Add images

    Drop up to 30 JPG, PNG, WebP or HEIC files, or tap to browse.

  2. 2.Pick quality or a size limit

    Use the quality slider, or switch to target size and type a limit such as 200 KB.

  3. 3.Download

    Save each file, or all of them in one ZIP. Changing a setting redoes every image straight away.

Example: a 12-megapixel phone photo for a website

A 4032 × 3024 photo straight from a phone camera, compressed for a blog:

Original
4032 × 3024 px, 12.2 megapixels
Longest side
1920 px → 1920 × 1440 px
Pixels kept
2.76 megapixels (77% fewer)
Quality
70% JPG
Typical result
about 250–450 KB, from 3–5 MB

Most of the saving comes from the smaller pixel size; the quality setting does the rest. The exact size depends on how much detail the photo has.

How the target-size mode works

In target-size mode the tool tries quality 95% first. If the file is too big, it narrows the quality down in seven halving steps to find the highest setting that still fits. If even 10% quality is too large, it shrinks the pixel size by 15% and searches again, so you get the best-looking image under the limit rather than the smallest possible one.

Compression here is lossy for JPG and WebP: fine detail that's hard to see is thrown away. Keep your original if you might edit or print the photo later.

Frequently asked questions

How do I compress a photo to under 100 KB for a form?

Choose To a target size, enter 100, and set Longest side to 1280 px or less. Smaller pixel sizes reach a limit at a higher quality than full-size photos.

Why did my PNG barely get smaller?

PNG is lossless, so re-saving it as PNG keeps every pixel. Switch Save as to WebP or JPG for savings of 70% or more on photos; keep PNG for logos and screenshots with sharp text.

Are my images uploaded anywhere?

No. The browser decodes and re-encodes them with its own canvas, so they stay on your device and work offline once the page has loaded.

What does "already compact, original kept" mean?

Re-saving an already well-compressed file at the same size and format would have made it bigger, so the tool gives you the original unchanged.

Does compression remove EXIF location data?

Yes for every re-encoded image: camera details and GPS location aren't carried over. The exception is a file marked as original kept, which is passed through untouched.

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