In this article
What Is Image Compression?
Image compression reduces the file size of a photo or graphic while preserving as much visual quality as possible. There are two main approaches: lossy compression, which discards some data for smaller files, and lossless compression, which preserves every pixel but achieves less reduction.
Compressed images load faster on websites, take less storage space, and are easier to share by email or messaging apps. For web developers, optimized images are critical for page speed scores and user experience.
How Our Compressor Works
CheckTown's image compressor runs entirely in your browser — no files are uploaded to any server. Here's what happens when you compress an image:
- Upload your image (JPEG, PNG, or WebP up to 50 MB) via drag-and-drop or file picker
- Adjust the quality slider to balance file size against visual fidelity — lower values mean smaller files
- Click Compress and instantly see the result with a side-by-side size comparison
Try it free — no signup required
Compress an Image →When To Use Image Compression
Compressing images is useful in many everyday and professional scenarios:
- Website optimization — reduce page weight so visitors experience faster load times and better Core Web Vitals scores
- Email attachments — shrink photos below common attachment limits (10–25 MB) without losing clarity
- Social media — compress images before uploading to avoid platform re-compression that can degrade quality unpredictably
Frequently Asked Questions
Does compression reduce image quality?
Lossy compression removes some data, so there is a small quality loss at aggressive settings. At 70–85 % quality the difference is usually imperceptible to the human eye while achieving 50–80 % file-size reduction.
Is my image uploaded to a server?
No. CheckTown processes everything in your browser using client-side JavaScript. Your image never leaves your device.
Which format should I choose for the smallest file?
WebP typically produces the smallest files at comparable quality, followed by JPEG. PNG is best when you need transparency or pixel-perfect graphics, but files are larger.