PNG vs JPG vs WebP vs AVIF: Which Image Format Should You Use in 2026?

If you're deciding which image format to use in 2026 — PNG, JPG, WebP, or AVIF — the short answer is: probably AVIF for photos, WebP as a fallback, PNG only when you genuinely need a lossless image with transparency, and JPG only when you're sharing with something that won't accept anything else. The longer answer (with the file-size benchmarks, browser support reality, and a decision tree at the bottom) is below.

This matters more than people think. The average web page in 2026 ships about 2.1 MB of images. Picking the right format — and compressing it client-side before upload — routinely cuts that in half without any visible quality loss. Faster pages, lower CDN bills, better Core Web Vitals.

A 30-second refresher on the four formats

JPG (also written JPEG) is the old reliable. It uses lossy compression — meaning each save throws away some data — and is best for photographs and other natural images with lots of colour gradients. It does not support transparency.

PNG is lossless. Each save preserves every pixel exactly. It supports transparency. The tradeoff: PNG files are usually 2–5× larger than the same image as a JPG. It's best for screenshots, logos, icons, and anything with hard edges or transparency.

WebP, released by Google in 2010 but only really widespread since around 2020, does both lossy and lossless compression. WebP files are typically 25–35% smaller than the equivalent JPG at the same visual quality, and 20–25% smaller than PNG for lossless images. It supports transparency. It's now supported by every modern browser.

AVIF, based on the AV1 video codec, is the newest of the four. Released to the web around 2019, it offers the best compression of all four formats — usually 40–50% smaller than JPG at the same visual quality, and 20% smaller than WebP. It supports transparency and HDR. Browser support is now universal (Safari shipped support in 2023, Edge and Firefox earlier).

File-size benchmarks (one photo, four formats)

Here's a 3000×2000 photograph of a landscape, compressed to "high quality" in each format:

Format	File size	% of original
PNG (lossless)	8.4 MB	100%
JPG (quality 85)	1.2 MB	14%
WebP (quality 85)	0.78 MB	9%
AVIF (quality 70)	0.51 MB	6%

A 14× reduction going from PNG to AVIF, with no perceptible difference at normal viewing sizes. For a screenshot with text or a logo, the savings shift — PNG is sometimes smaller than WebP for very simple graphics — so always test on your actual images.

If you want to see the numbers on your own image, drop it into the image format converter — it'll convert and report file sizes for all four formats side by side, all in your browser.

When to use each format in 2026

Use AVIF when:

You're serving images on a modern website and care about page weight
You're shipping photos or any image with lots of gradients
You can provide a WebP or JPG fallback for older browsers (the <picture> element makes this trivial)

Use WebP when:

You need broad browser support but don't want to ship 2024-era file sizes
You're updating an existing site and want a one-format swap (WebP support is essentially universal in 2026)
Your CMS or build pipeline doesn't yet emit AVIF

Use PNG when:

The image has hard edges or text where lossy artefacts would show (UI screenshots, logos, diagrams)
You need true lossless quality — e.g. archiving design assets, source images
You need transparency and you're shipping to a place that doesn't support WebP or AVIF (rare in 2026)

Use JPG when:

You're sharing with a tool, platform, or recipient that doesn't accept newer formats (some print-on-demand services, some legacy CMSes, some email clients)
You're optimising for absolute compatibility over file size

Notable exception: for vector logos and icons, use SVG — none of these four formats are the right answer. If you have a PNG logo and want it as a true vector, that's a redraw, not a conversion. But if your "vector" is locked inside an SVG and you need a raster export for a thumbnail, our SVG to PNG converter handles that without uploading the SVG anywhere.

Browser support reality (May 2026)

Here's the truth — and it's good news:

JPG, PNG, WebP, AVIF: all four are supported in 100% of modern browsers, including Safari, Chrome, Edge, Firefox, and mobile equivalents.
The only real "non-support" scenarios in 2026 are:
- Very old Android WebViews (pre-2022) — < 0.5% of traffic
- Email clients (Outlook, some webmail) — many still don't render AVIF in inline images. JPG/PNG remain safer for email.
- Some print-on-demand and document-generation tools — these often want PNG or JPG specifically.

For 99% of the open web, you can ship AVIF as the primary and WebP as a fallback and be done.

A decision tree for the lazy

Is it a photo? → AVIF first, WebP fallback, JPG legacy fallback.
Is it a screenshot, logo, or diagram with hard edges? → PNG, or WebP-lossless if file size matters more than perfect fidelity.
Does it need transparency? → AVIF, WebP, or PNG (all three support it). Not JPG.
Is it a logo or icon you'll scale? → SVG, not a raster format.
Are you uploading to a legacy system or email? → JPG or PNG, whichever the system prefers.

How to actually convert (without uploading your images anywhere)

The friction with most online image converters is that they require you to upload the image to a server. For a holiday photo that's fine. For a product mockup, an internal diagram, or anything with sensitive content, it's a real problem — you're handing your image to a third party.

Stax Tools runs every image conversion entirely in your browser. The image data never leaves your device. Three tools cover the practical cases:

Image Format Converter — convert any image to or from JPG, PNG, WebP, or AVIF. Side-by-side file-size comparison.
Image Compressor — compress JPG/PNG/WebP at a quality you control, without changing format. Useful when you're constrained to a specific format.
TinyPNG Alternative — drop-in replacement for TinyPNG with PNG and JPG optimisation, but client-side. Same compression, none of the upload.

TL;DR

For most images in 2026, AVIF for photos and WebP for everything else is the right default. Keep PNG for hard-edged graphics with transparency, and JPG only when something downstream needs it.

→ Convert your images to the right format now — free, in-browser, no upload.