PNG vs JPG vs WebP vs AVIF: Which Format Should You Use?

Four image formats dominate the modern web, and the advice about them is often weirdly tribal. In reality each format is a tool with a job it does best. This comparison skips the dogma and looks at what PNG, JPG, WebP and AVIF are actually good at, what they cost, and how to choose in ten seconds for any given image.

JPEG (JPG): the universal workhorse

JPEG has been the default photo format since 1992, and its compression model still holds up: it divides the image into 8×8 blocks and stores them as frequency components, throwing away the ones humans barely perceive. At quality 80–85 a JPEG photo looks identical to the original at a fifth of the size.

Strengths: universal support — every device, browser, CMS, email client and printer pipeline on Earth opens JPEG. Efficient for continuous-tone photographs. Weaknesses: no transparency, lossy only, and visible block artifacts around sharp edges and text. Re-saving a JPEG repeatedly compounds the damage.

Use it for: photographs that must work absolutely everywhere — email attachments, marketplace listings, form uploads, print.

PNG: the lossless perfectionist

PNG compresses with DEFLATE, the same algorithm inside ZIP files. Nothing is ever discarded: decode a PNG and you get the original pixels back bit-for-bit. It also supports full alpha transparency, which is why it became the format of the design world.

Strengths: lossless, transparent backgrounds, crisp on text, line art, logos and screenshots. Weaknesses: photographs balloon — a photo that is 300 KB as JPEG can be 3 MB as PNG. No animation (that is APNG, a later extension with patchy tooling).

Use it for: screenshots, interface graphics, logos, icons, diagrams, anything with text or transparency. Avoid it for: photos destined for the web.

WebP: the pragmatic upgrade

Google released WebP in 2010 to be a single format that does both jobs: a lossy mode based on the VP8 video codec, and a lossless mode that beats PNG by roughly 25%. It supports transparency in both modes, plus animation. Browser support is now effectively universal — every current browser has rendered WebP for years.

In practice, WebP has become the quiet default of the performance-minded web: CDNs generate it automatically, WordPress and most static-site tooling emit it, and design tools export it. If you only have the appetite to adopt one newer format, make it this one — the savings are immediate and the compatibility risk is close to zero.

Strengths: 25–35% smaller than JPEG at equal visual quality; lossless mode smaller than PNG; transparency and animation in one format. Weaknesses: some older desktop software (legacy Office, old image viewers) cannot open it; maximum dimensions are capped at 16383×16383 pixels.

Use it for: almost everything on the web. It is the best default choice for sites in 2026: photos, graphics and transparent assets all get smaller.

AVIF: the aggressive newcomer

AVIF packages frames from the AV1 video codec as still images, and the compression is remarkable — files routinely come out 40–50% smaller than equivalent JPEGs, beating even WebP. It supports 10-bit and 12-bit color, HDR, transparency and animation.

Netflix, which funded much of AV1's development, has used AVIF for artwork precisely because those savings multiply across billions of image requests.

Strengths: best-in-class compression, future-proof color depth. Weaknesses: encoding is computationally expensive (slow on the server or device), support in non-browser software is still catching up, and at very low bitrates AVIF tends to smooth textures in a way some people find artificial.

Use it for: hero images and photo-heavy pages where every kilobyte matters — ideally served with a WebP or JPEG fallback via the <picture> element.

The ten-second decision guide

• Photograph for the web → WebP (AVIF if you can provide a fallback).
• Photograph for email, print, or someone else's ancient system → JPEG.
• Screenshot, logo, text, transparency needed → PNG (or lossless WebP if the destination supports it).
• Animation → WebP (smaller than GIF, and supports real color).

Serving modern formats without leaving anyone behind

If you run a website, you do not have to choose one format for everyone. The HTML <picture> element lets the browser pick the first source it understands: offer AVIF, then WebP, then JPEG, and every visitor gets the smallest file their browser can decode. Most CDNs can even do this negotiation automatically from a single original. The rule of thumb for 2026: generate AVIF and WebP for image-heavy pages, keep a JPEG fallback, and keep PNG only for graphics that genuinely need lossless pixels or transparency.

Try the difference yourself

Theory is nice; numbers are better. Drop any image into our Format Converter and flip between PNG, JPEG, WebP and AVIF — the resulting file size updates live, so you can see exactly what each format costs for your image rather than trusting generalities. The conversion runs entirely in your browser, so testing confidential artwork is safe too.