Image Compressor
Compress JPG, PNG and WebP images in your browser with an adjustable quality slider. See before/after file size and download the smaller image free.
What is the Image Compressor?
The ByteTools Image Compressor shrinks JPG, PNG and WebP files by re-encoding them on an HTML5 canvas at the quality level you choose.
- Adjustable quality slider from 1 to 100
- Outputs JPEG or WebP for maximum savings
- Live before/after file size comparison with savings percentage
- Side-by-side preview of the original and compressed image
- 100% private — images never leave your browser
- Free, unlimited use with no watermarks or sign-up
How to use the Image Compressor
- 1
Drop a JPG, PNG or WebP image into the upload area or click to browse.
- 2
Move the quality slider — lower values give smaller files, higher values keep more detail.
- 3
Choose JPEG or WebP as the output format and click Compress image.
- 4
Compare the before and after sizes, then click Download to save the compressed file.
About the Image Compressor
The ByteTools Image Compressor shrinks JPG, PNG and WebP files by re-encoding them on an HTML5 canvas at the quality level you choose. Drag a photo in, move the quality slider, and instantly compare the original and compressed file sizes before downloading the result.
It is built for bloggers, web developers and anyone emailing photos or uploading them to sites with strict size limits. Smaller images mean faster page loads, better Core Web Vitals and higher search rankings.
Compression happens 100% locally in your browser — your photos are never uploaded to a server, so private pictures, client work and unpublished designs stay on your device.
Frequently asked questions
How can I compress an image without losing quality?
Keep the quality slider between 75 and 85 — at that range JPEG and WebP compression removes data your eyes barely notice, often cutting the file size by 50–80%. Compare the preview against the original before downloading to make sure it still looks sharp.
What is the best quality setting for web images?
Quality 70–80 is the sweet spot for most photos on the web: files get dramatically smaller while artifacts remain nearly invisible. For hero images or photography portfolios use 85–90; for thumbnails you can go as low as 50–60.
Does compressing a PNG make it a JPEG?
This tool re-encodes your image as JPEG or WebP because those lossy formats compress far better than PNG for photos. Note that JPEG has no transparency, so transparent PNG areas become white — choose WebP if you need to keep transparency with strong compression.
Are my images uploaded to a server when I compress them?
No. All compression runs in your browser using the HTML5 canvas API. The image never leaves your computer, so it is completely safe for private photos and confidential design work.
Why is my compressed image bigger than the original?
If the original was already heavily compressed, re-encoding at a high quality setting can produce a larger file. Lower the quality slider, or try WebP output, which usually beats JPEG at the same visual quality by 25–35%.
Guides for Image Compressor
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