JPG vs PNG vs WebP: Which Image Format Should You Use?
Choose an image format based on content, transparency, compatibility and file-size goals rather than habit.
JPG is built for photographs
JPEG uses lossy compression that works well on continuous-tone photography. It can make photos much smaller, but repeated saves and low quality settings create blockiness and ringing around sharp edges.
PNG protects exact pixels and transparency
PNG is lossless and supports alpha transparency. It is strong for logos, line art, UI screenshots and graphics with flat colors. It can be inefficient for detailed photographs.
WebP bridges several use cases
WebP can support lossy photo compression, lossless compression and transparency. Modern browsers handle it well, making it useful for web delivery. Compatibility with older desktop software can still be a reason to keep JPEG or PNG copies.
Do not expect format conversion to restore quality
Saving a damaged JPEG as PNG stops additional JPEG loss but does not reconstruct detail already discarded. Likewise, converting a PNG to JPEG permanently removes transparency.
Quick decision rule
Photo with no transparency: JPG or WebP. Logo/graphic with transparency: PNG or WebP. Screenshot with tiny text: compare PNG and lossless WebP. Unknown downstream software: JPEG/PNG remain safest.
A task you can work through
Consider three assets for a website: a restaurant photo, a flat logo with transparent space, and a screenshot with 9-point text. For the photo, export JPEG and WebP at the same pixel dimensions, then compare visible detail and file sizes. For the logo, use PNG or a WebP export that preserves alpha transparency. For the screenshot, inspect tiny letters at 100% before choosing lossless PNG or WebP. The file extension alone says little about whether the output fits the content.
Where this approach fails
A JPEG has no alpha channel. Changing its name to PNG or running JPG to PNG does not invent a transparent background or recover blocky edges. PNG to JPG replaces transparency with a background color and introduces lossy compression. Some older software or upload portals reject WebP even if modern browsers display it correctly. Keep an original editable master, then produce destination-specific copies; do not repeatedly convert the same lossy copy.
Check the result before using it
Compare dimensions, transparency and byte size of the exported files. Test the exact upload target or email client, not just a browser preview. For a logo, inspect edges against both light and dark backgrounds. For a photo, compare faces, hair and textured areas at the final display size. If compatibility is uncertain, keep a JPEG or PNG fallback.
Compare a fair pair
To compare formats, hold pixel dimensions and visual target constant. Export a 1600 by 900 photograph as JPEG and WebP, view both at their final display size and compare bytes; a tiny WebP file with obvious artifacts is not the same-quality comparison. For a screenshot, compare PNG with lossless WebP so text and edges remain exact. For a transparent logo, inspect the alpha edge on dark and light backgrounds. The appropriate format is the smallest compatible file that meets the visual requirement.
Practical delivery matrix
Use JPEG when broad compatibility and photographs matter more than transparency. Use PNG for exact pixels, UI screenshots and transparency when compatibility is the priority. Consider WebP for web delivery when the destination supports it and a measured size saving appears. A PDF, Word file or print vendor can have its own accepted formats, so check the final destination. Keep an editable source or high-quality original so future exports do not start from a lossy derivative.
Try the related tool
Convert images to and from the WebP format. The tool page explains its implementation and limitations. Keep your original and inspect any important result.
WebP Converter →Technical references
These external references explain the underlying formats or browser APIs. The worked examples above describe this site's specific tool behavior.