Compress images without losing quality
“Without losing quality” usually means without a visible loss at the size where the image will be used. Every image has a different file-size floor, but a careful workflow can remove substantial weight while keeping the details people actually notice.
Start with dimensions, not only quality
A camera photo can be thousands of pixels wider than a website, profile card or application preview needs. Resizing excessive dimensions often saves more data cleanly than forcing a full-resolution image through very low encoding quality.
Match the pixel dimensions to the largest real display size. Keep a separate original for print, editing or future uses that need more resolution.
Choose a format that fits the content
JPG is usually efficient for photographs. PNG protects crisp text, flat graphics and transparency. WebP can handle both photos and transparency with efficient modern compression.
Changing a photo from JPG to PNG does not restore lost detail and normally makes it larger. Choose the format based on the pixels and the destination’s compatibility rules.
- Photos: JPG or WebP
- Screenshots and diagrams: PNG
- Transparent web graphics: PNG or WebP
- Strict forms: use the exact requested format
Avoid generation loss
Every lossy save starts from the pixels in the current file. Compressing an already compressed copy again can amplify blocks, ringing and smeared texture.
Keep one clean source and create each smaller version directly from it. Inspect the result at normal viewing size before deciding whether the saving is worth the visual change.