WEBP vs PNG vs JPG vs AVIF

• Sending or uploading a photo anywhere: JPG.
• Screenshot, logo, diagram, text, transparent background: PNG.
• Images on your own website: WEBP, or AVIF if you can afford slower encoding.
• A form or an old app rejects your file: convert to JPG (photos) or PNG (graphics).

The rest of this guide explains why, and where each rule breaks.

JPG (or JPEG, same thing) dates from 1992 and opens on every device, app, printer and upload form. It compresses photos well by throwing away detail the eye barely notices. At quality 85–90 the loss is invisible at normal size; below about 60 you start to see blocky patches and halos around edges.

Limits: no transparency, no animation, 8-bit colour, and each re-save loses a little more. Sharp edges and text get soft fringes, which is why screenshots look worse as JPG. Use it for photos you share, and keep originals if you plan to edit repeatedly.

PNG is lossless: what you save is exactly what you get back, pixel for pixel. It supports full transparency (smooth edges against any background) and is the right home for screenshots, UI, logos, line art, charts and anything with text.

The catch is size on photos. Lossless compression cannot do much with the fine noise of a camera image, so a photo as PNG is typically 3–5 times larger than as JPG and looks no better. Converting a JPG to PNG does not restore detail; it just stores the existing pixels without further loss, which is useful before editing.

WEBP was made for websites. It has a lossy mode for photos, about 25–35% smaller than JPG at the same visible quality, and a lossless mode for graphics, usually smaller than PNG. It supports transparency in both modes, and animation.

All current browsers display it, and most phones and modern apps open it. The friction is elsewhere: some older editors, office suites, print services and upload forms still refuse WEBP. That is why so many people save an image from a website and then need WEBP to PNG or WEBP to JPG. For your own site, WEBP is a safe default today.

AVIF stores images compressed with the AV1 video codec inside the HEIF container. It usually beats WEBP by another 20% or more at the same quality, handles 10- and 12-bit colour and HDR, and supports transparency and animation. The codec is royalty-free, which is why browsers adopted it and not HEIC.

The costs: encoding is slow, often seconds per photo on a phone, and support outside browsers lags behind WEBP. Some apps and many forms still cannot open AVIF. Use it for websites where every kilobyte counts and you control the encoding; convert AVIF to JPG when you need to share it.

• Photo file size (lower is better): AVIF smallest, then WEBP, then JPG; PNG is several times larger.
• Lossless option: PNG yes; WEBP yes; AVIF yes; JPG no.
• Transparency: PNG, WEBP, AVIF yes; JPG no.
• Animation: WEBP and AVIF yes; PNG only as APNG, with mixed app support; JPG no (GIF is the old option).
• Colour depth: JPG and WEBP 8-bit; PNG up to 16-bit; AVIF up to 12-bit with HDR.
• Encoding speed: JPG and PNG fast; WEBP fast; AVIF slow.
• Opens in every app and form: JPG and PNG yes; WEBP mostly; AVIF in browsers, less elsewhere.

When you convert a transparent PNG, WEBP or AVIF to JPG, the transparent areas must become a solid colour, because JPG has no alpha channel. KiteConvert fills them with white by default and lets you pick another colour. Converting between PNG, WEBP and AVIF keeps transparency.

Animated WEBP and GIF files are another trap: converting them to a still format keeps only the first frame, and our converter tells you when that happens. To keep the motion, convert to MP4 video instead, which is far smaller than GIF anyway.

• JPG: quality 85–90 for photos you keep, 75–80 for the web, around 60 when a strict size limit forces it.
• WEBP: 80–85 looks like a JPG at 90 and is noticeably smaller.
• AVIF: 50–65 is already high quality; numbers are not comparable with JPG quality.
• PNG: no quality setting; size depends on the picture. For screenshots, the compress tool can reduce the colours for much smaller files.
• Dimensions matter more than format: a 4000-pixel photo shown 1200 pixels wide wastes most of its bytes in any format. Set a maximum width first, then pick the format.

• Lossy to lossless (JPG, WEBP or AVIF to PNG): no further loss, but no gain either, and the file grows.
• Lossless to lossy (PNG to JPG, WEBP or AVIF): one round of compression, invisible at the settings above, with transparency filled in for JPG.
• Lossy to lossy (WEBP to JPG, JPG to AVIF): a second round of compression. At high quality it is not visible, but avoid doing it again and again on the same picture.
• Metadata: JPG outputs from KiteConvert keep the date taken by default; PNG, WEBP and AVIF outputs carry no photo metadata. GPS is removed by default either way.

The practical rule: convert from the best original you have, once, to the format the destination needs.