# Image Compressor — Shrink to Any Target Size or Dimensions

> Drop an image, see its current size and dimensions auto-detected, then set your targets and compress.

Drop an image and the tool auto-detects its width, height and file size. Edit the target width, height or file size to compress — the tool binary-searches for the best quality to hit your KB goal. Everything runs in your browser.

**URL:** https://convertto.tech/t/image-compressor
**Category:** Image Tools (https://convertto.tech/c/image-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Auto-detect:** Fills width, height and file size from the image on drop
- **Target size:** Auto-adjusts quality in up to 8 passes to hit your KB goal
- **Batch:** Multiple images in one go
- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Select your images — the file stays on your device and is never uploaded.
2. Set the target width.
3. Set the target height.
4. Set the target file size.
5. Set the quality.
6. Choose the output format.
7. Pick the background.
8. Press Run, then download the result when it is ready.

## FAQ

### How does it know what quality to use?

If the result at your chosen quality is already under the target file size, it keeps that quality. Otherwise it binary-searches downward — trying progressively lower quality levels — until it finds the highest one that stays at or below your target KB.

### What quality setting should I use?

For photographs on the web, 70–80 % is usually indistinguishable from the original at roughly a third of the size. Screenshots and graphics with sharp edges hold up better in PNG or at higher WebP quality.

### Why did my PNG get bigger?

Re-encoding an already-optimised PNG as PNG can add bytes. For photographs, switch the output format to WebP or JPG — PNG is a lossless format and cannot compete on size for photographic content.

### Can I compress an image to exactly 100 KB?

Set the target file size to 100. The tool will find the highest quality that keeps the file at or below 100 KB. If the original is already smaller, no change is needed.

## Related tools

- [SVG Optimizer](https://convertto.tech/t/svg-optimizer): Strip editor cruft and optimise path data to cut SVG file size, usually by half or more.
- [HTML, CSS & JS Minifier](https://convertto.tech/t/code-minifier): Strip whitespace and comments to shrink HTML, CSS and JavaScript for production.
- [AVIF Converter](https://convertto.tech/t/avif-converter): Convert images to and from AVIF in your browser, with a real encoder check so you never get a PNG renamed to .avif.
- [Compress PDF](https://convertto.tech/t/compress-pdf): Reduce PDF file size by re-rendering pages at a lower resolution and quality.
- [Video Compressor](https://convertto.tech/t/video-compressor): Shrink video file size with adjustable quality — locally, with no upload limit.
- [Aspect Ratio Calculator](https://convertto.tech/t/aspect-ratio-calculator): Work out the aspect ratio of any dimensions and scale them proportionally.
- [EXIF Remover](https://convertto.tech/t/exif-remover): Strip all metadata — including GPS location — from photos before sharing them.
- [Favicon Generator](https://convertto.tech/t/favicon-generator): Turn any image into a complete favicon set with all the sizes modern browsers expect.