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

You exported a logo as JPG and the edges turned fuzzy. You saved a photo as PNG and it ballooned to 12 MB. Picking the wrong image format costs you quality, bandwidth, or both. This guide settles PNG vs JPG vs WebP vs AVIF for 2026: what each format is actually built for, how much smaller the modern formats really are, how widely they're supported now, and a fast rule for choosing in any situation.

#TL;DR

• PNG: lossless, supports transparency — use for logos, icons, screenshots, sharp-edged graphics.
• JPG: lossy, no transparency — use for photographs where small size matters.
• WebP: does both lossy and lossless, plus alpha and animation — a strict upgrade on JPG/PNG.
• AVIF: smallest files for photos, adds HDR and wide color — best modern choice with a fallback.
• Serve AVIF → WebP → JPG/PNG with <picture>, and let the browser pick.

#PNG vs JPG vs WebP vs AVIF: a 2026 cheat sheet

The four formats split cleanly into two old standbys (PNG, JPG) and two modern codecs (WebP, AVIF). Knowing which bucket your image belongs in answers most of the question before you compare a single byte.

Here's the one-screen version:

#What "lossy" and "lossless" really mean

A lossless format reconstructs every original pixel exactly — decode the file and the raster is bit-for-bit identical. PNG is lossless by design; its spec, RFC 2083, guarantees it. A lossy format like JPG throws away detail the eye is unlikely to notice, using a discrete cosine transform (DCT) to trade fidelity for size. Every re-save of a JPG degrades it a little more.

WebP and AVIF are interesting because they do both. You can encode them lossy for photos or lossless for graphics, getting the size win without committing to one mode for everything.

#Transparency and animation support

PNG popularized alpha transparency, and JPG never gained it — that single fact decides a lot of format choices. Both WebP and AVIF support full alpha channels, so a transparent overlay no longer forces you onto heavyweight PNG. For animation, animated PNG (APNG), WebP, and AVIF all exist, but in practice animated WebP remains the most reliable cross-browser option in 2026.

#Browser support in 2026

This used to be the dealbreaker for the modern formats. It isn't anymore. Per caniuse, WebP is supported by essentially every browser in use today — well above 97% globally. AVIF support has climbed to roughly 95%, with Chrome, Edge, Firefox, Safari, and Opera all decoding it natively. The remaining gap is small enough that a one-line fallback covers it.

#When should you use PNG instead of JPG?

The classic mistake is reaching for JPG out of habit because "it's smaller." For the right image it is — for the wrong one it's both larger and worse-looking.

#Use PNG when the image has

• Transparency — any logo, badge, or sticker that sits over a background.
• Sharp edges or text — UI screenshots, diagrams, charts, code snippets.
• Few colors / flat fills — illustrations and icons compress beautifully losslessly.
• A need for exact pixels — anything you'll edit again or hash for integrity.

#Use JPG when the image is

A continuous-tone photograph — a person, a landscape, a product shot with soft gradients and no hard edges. JPG's DCT was tuned for exactly this content, and at quality 75–85 it produces small files most people can't distinguish from the original. There's no transparency, so JPG is purely a "final photo for delivery" format.

#The transparency trap

If you flatten a transparent PNG into JPG, the alpha channel doesn't degrade gracefully — it gets filled with a solid color (usually black or white), often wrecking the image. Per the MDN image format guide, JPG simply has no concept of an alpha channel. If you need both small size and transparency, that's the exact gap WebP and AVIF fill.

#Is AVIF better than WebP in 2026?

For the common case — compressing photographs for the web — AVIF is now the stronger format. But "better" depends on what you're optimizing for, and WebP still wins a few categories.

#How much smaller AVIF really is

Google's own WebP compression study found lossy WebP images run 25–34% smaller than JPG at equivalent quality, and its lossless study reports lossless WebP about 26% smaller than PNG. AVIF pushes further: web.dev's image guidance describes AVIF reaching roughly a median 50% reduction versus JPG, compared with about 30% for WebP on the same set. Translated to a real workload, 100 photos that weigh ~130 MB as JPG land near ~60 MB as WebP and ~36 MB as AVIF.

#Where WebP still wins

AVIF isn't a clean sweep. WebP encodes much faster, which matters when you're processing thousands of images in a build step. Its browser support is still a hair wider. And for very simple graphics or already-small images, WebP's lossless mode can occasionally edge out AVIF. WebP is also the safer pick for animation today.

#Encoding features and color

AVIF earns its size win partly through the AV1 codec, and it brings features JPG and WebP can't match. The AV1 Image File Format specification — maintained by the Alliance for Open Media and royalty-free — supports high dynamic range (HDR), wide color gamut, monochrome, alpha, and high bit depths. If you're shipping HDR photography or 10-bit gradients, AVIF is the only one of the four that carries them properly.

#How to convert PNG to WebP without losing quality

Converting is the easy part — the trick is converting losslessly where it matters and lossy where it pays off. You don't need Photoshop or a build pipeline for one-off jobs.

#Convert in the browser, no upload

The fastest path is a client-side converter. iKit's Image Format Converter runs entirely in your browser — your file never leaves your device — and turns PNG, JPG, WebP, and AVIF into each other in a couple of clicks. Choose lossless when converting graphics and logos so edges stay perfect; choose a quality slider around 75–85 for photos to capture the size win. If your goal is just shrinking files in the format you already have, the Image Compressor batch-compresses and zips a whole folder at once.

#Serve modern formats with <picture>

For websites, don't pick one format — let the browser choose the best it supports. The MDN-recommended pattern lists AVIF first, WebP next, and a JPG fallback in the <img>:

<picture>
  <source srcset="hero.avif" type="image/avif">
  <source srcset="hero.webp" type="image/webp">
  <img src="hero.jpg" alt="Mountain at dawn"
       width="1200" height="630">
</picture>

The browser walks the <source> list top to bottom and uses the first type it understands, falling back to the <img> if it supports none. That's how you ship AVIF to 95% of visitors and JPG to the rest with zero JavaScript. Resize to the dimensions you actually display before converting — a 4000px photo scaled down with the Image Resizer compresses far smaller than the full-resolution original in any format.

On the command line, the same conversion looks like this:

# PNG/JPG to WebP (lossless for graphics)
cwebp -lossless logo.png -o logo.webp

# JPG to AVIF (quality ~60 ≈ JPG q85)
avifenc --min 20 --max 30 photo.jpg photo.avif

#Why is my converted JPG bigger than the original PNG?

This surprises people constantly. You convert a 200 KB PNG screenshot to JPG expecting it to shrink, and it comes out at 400 KB and looks worse. The reason: JPG's lossy DCT is built for soft photographic gradients, and it handles the sharp edges, flat color blocks, and crisp text of a screenshot terribly — it spends bytes trying to encode high-frequency edges it can't represent cleanly. For that image, lossless PNG or WebP lossless is genuinely smaller. The lesson: format size depends on content, not on which format is "newer." Photographs → JPG/WebP/AVIF; flat graphics and text → PNG/WebP lossless.

#References

• Image file type and format guide — MDN — authoritative overview of PNG, JPG, WebP, and AVIF capabilities and the <picture> fallback pattern.
• WebP Compression Study — Google for Developers — source for the 25–34% lossy WebP-vs-JPG file-size figures.
• Lossless and Transparency Encoding in WebP — Google for Developers — source for lossless WebP being ~26% smaller than PNG.
• AV1 Image File Format (AVIF) specification — Alliance for Open Media — confirms AVIF's royalty-free status, HDR, wide-gamut, alpha, and bit-depth support.
• AVIF image format — Can I use — current ~95% global browser-support figure for AVIF.
• Image formats: WebP — web.dev — comparative AVIF-vs-WebP compression guidance.

#Related on iKit

• Compress PNG images without losing a single pixel — the lossless side of PNG, and exactly when WebP lossless beats it for the same image.
• Batch-compress JPG, PNG, and WebP into one ZIP — once you've picked a format, squeeze a whole folder at once in the browser.
• Resize images for Instagram, X, and LinkedIn — format and dimensions are two separate decisions; this covers the dimensions side.
• Remove an image background without Photoshop — the most common reason you need a transparent PNG or WebP in the first place.