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

Start with the kind of image you have

Photographs contain continuous tones and subtle texture, which lossy compression can reduce efficiently. Logos, screenshots and diagrams often contain flat colour, hard edges and text, where compression artifacts are easier to notice. Images with transparent backgrounds need a format that can store an alpha channel.

The source matters too. If a JPEG has already been compressed heavily, converting it to PNG creates a larger file but does not restore missing detail. Likewise, repeatedly converting between lossy formats can compound artifacts. Keep the highest-quality original and create delivery versions from that master.

JPEG: broad compatibility for photographs

JPEG is one of the safest choices when a photographic image must open almost everywhere. It uses lossy compression, so file size can be reduced substantially by discarding visual information. At sensible quality settings the loss may be hard to notice at normal viewing size; at aggressive settings, blocking, ringing and softened detail become visible.

JPEG does not support transparency. It is also not ideal for repeated editing and re-saving because each lossy export can remove more information. Use it for ordinary photo delivery, email attachments and compatible web images when transparency is unnecessary.

PNG: lossless pixels and transparency

PNG stores raster images losslessly and supports transparency. It is a strong choice for screenshots, interface graphics, line art, diagrams and logos that need crisp edges. Because it preserves the pixel data rather than approximating it with JPEG-style compression, photographic PNGs can be much larger.

PNG is useful as an intermediate or master for certain graphics, but it is not automatically “higher quality” than the source. Saving a damaged or compressed JPEG as PNG preserves the current pixels exactly; it does not recreate the original camera data.

WebP and AVIF: efficient modern delivery formats

WebP supports lossy and lossless compression as well as transparency, which makes it flexible for the web. AVIF can be even more efficient for many photographic images and also supports transparency, but encoding may take longer and compatibility with older software can be less predictable than JPEG or PNG.

For a website you control, modern formats can reduce transfer size. For client handoff, print labs, older desktop applications or long-term interoperability, a JPEG or PNG copy may still be useful even if the web version uses WebP or AVIF.

GIF: useful for a narrow set of jobs

GIF is limited to a 256-colour palette per frame and is best known for simple animation. It is inefficient for full-colour photographs compared with modern formats. A static GIF can be converted to PNG or WebP for many use cases, while animated GIFs require a workflow that preserves animation rather than treating only one frame.

If your priority is lightweight animation on a modern site, video formats can sometimes be more efficient than GIF. The right answer depends on where the media will be embedded and what that platform accepts.

A practical decision checklist

• Photograph for broad sharing: JPEG is usually the safest starting point.
• Transparent logo or screenshot: PNG or WebP.
• Website performance: consider WebP or AVIF, then test the actual visual result.
• Editing master: keep the best original rather than repeatedly converting a delivery copy.
• Unknown recipient software: favour compatibility and provide a JPEG or PNG when needed.

Keep the original and verify the result

File conversion is most reliable when the source is preserved until the new file has been checked in its real destination. If a document, image, subtitle or media file has legal, archival or production value, keep the original separately and treat the converted version as a derivative copy.