JPG vs PNG vs WebP: which format should you use?

JPG

Choose JPG for photographs and broad compatibility

JPG is designed for continuous-tone imagery such as photographs. Its lossy encoder can create compact files by simplifying information people are less likely to notice. At sensible quality settings it remains a dependable choice for email attachments, marketplace photos and systems with strict format support.

JPG has no transparency channel. When a transparent PNG or WebP is converted to JPG, the transparent area must be filled with a real color. ResizeImg asks you to choose that background first so the result is predictable.

• Strong fit: photographs, social images and compatibility.
• Weak fit: logos with transparency, repeated editing and pixel-perfect graphics.

PNG

Choose PNG for transparency and lossless graphics

PNG preserves pixel information without JPEG-style quality loss and supports an alpha channel for transparency. It is useful for interface elements, logos, diagrams, screenshots and artwork with hard edges or transparent backgrounds.

Lossless does not mean small. Detailed photographs saved as PNG can be much larger than equivalent JPG or WebP files. Converting an existing JPG to PNG also does not restore detail; it only avoids adding another lossy encoding step to the already decoded pixels.

• Strong fit: transparency, screenshots, logos and crisp graphics.
• Weak fit: large photographic libraries where transfer size matters.

WebP

Choose WebP for efficient modern web delivery

WebP supports lossy photographic compression and transparency, allowing it to cover many jobs handled separately by JPG and PNG. It is often a practical website format when the content management system, browser audience and downstream workflow accept it.

Compatibility is now broad, but the final destination still matters. Some document tools, older desktop applications and upload forms may ask specifically for JPG or PNG. Keep a source file in a widely editable format when future reuse is important.

• Strong fit: modern sites, mixed image libraries and transparent web graphics.
• Weak fit: workflows that explicitly reject WebP.

A practical decision

Test the actual image instead of relying on a slogan

A noisy night photograph, a flat icon and a screenshot with text behave differently. Export a candidate in the formats your destination accepts, compare file size and inspect each result at its real display size. The winner is the smallest file that preserves the details important to that specific image.

Avoid converting repeatedly between lossy formats during editing. Keep an original, perform the visual changes, then create delivery versions at the end. This protects you from accumulating compression artifacts across multiple saves.