Image Compressor
Compresses JPEG images by adjusting quality to reduce file size in the browser.
Drop an image here, or
Processed in your browser — never uploaded.
Designed to process your files locally in your browser. Zerdly does not intentionally upload or store them unless this page says otherwise.
How to use this calculator
- Choose an image.
- Set the JPEG quality, then Compress and download.
How it works
Re-saves your image as a JPEG at the quality you choose — lower quality means a smaller file. All in your browser.
Worked example
70% quality. often halves a photo's size with little visible change.
Common mistakes
- Pushing quality too low to chase file size — artefacts and banding appear well before you save much more.
- Compressing an already-small PNG as JPEG and adding artefacts for little gain.
Frequently asked questions
How does image compression work here?
It re-encodes the image at a quality you choose, trading a little detail for a smaller file — all in your browser, nothing uploaded.
How much can I compress without it looking bad?
Photos often shrink 50–70% at a quality around 70–80% with little visible loss; preview before saving to find the sweet spot.
Will compressing reduce quality?
JPEG compression is lossy, so lower settings trade quality for size. Around 70–80% usually shrinks files a lot with little visible difference.
Related tools
- Image Resizer
- Image Converter
- Image DPI / Print Size Calculator
- Local PDF Merge Tool
- PDF Page Counter & Size Checker
- Delete PDF Pages Tool
Explore more in PDF, Image, File, Data & Developer Tools.
Cite this tool
Zerdly. (2026). Image Compressor. Retrieved from https://www.zerdly.com/tools/image-compressor/
Tip: Enter any known values to calculate the remaining results.
Designed to run locally in your browser. Tool inputs are not intentionally stored by Zerdly unless stated otherwise.