Why does my WebP look worse than my JPEG at the same file size?

Almost always because the quality setting numbers don't map across formats. 'Quality 85' in JPEG and 'Quality 85' in WebP produce different bitrates. A same-size comparison can be unfair to WebP. SnapToolz Convert Image has a 'match quality' mode that uses perceptual-quality-matched encodes so the comparison is honest.

Should I just convert all my old JPEGs to AVIF to save space?

Probably not. Re-encoding a lossy format to another lossy format generationally loses quality (the second encoder sees the artifacts of the first as 'real detail' and tries to preserve them). You'll save some bytes but the per-byte quality goes down. AVIF is best applied to a high-quality source — the original RAW or PNG — not as a re-encode of an old JPEG.

Does AVIF support animation like GIF?

Yes — animated AVIF exists, with full color depth and alpha. File sizes are dramatically smaller than animated GIF (often 10x smaller for the same animation). Browser support for animated AVIF lags the still-image case slightly; on important surfaces you may still want an MP4 or WebM as the fallback for animation.

I exported a screenshot as JPEG and the text looks fuzzy — why?

JPEG's frequency-domain compression hates sharp edges. Text on a flat background is the worst case for it: every letter edge becomes a high-frequency component that the encoder either preserves at high bitrate or smears into ringing artifacts. Use PNG, WebP lossless, or AVIF lossless for screenshots of text.

JPG vs PNG vs WebP vs AVIF — the 2026 image format decision guide · SnapToolz Guides

A quick tour of how we got four formats

JPEG arrived in 1992. It was designed for photographs — for content where the human eye won't notice small errors in color and luminance — and it uses a frequency-domain transform (DCT) to throw away the bits you can't see. Thirty-four years later it is still the universal format. Every operating system, every browser, every email client, every printer, every digital frame reads JPEG without question. That ubiquity is its biggest single feature.

PNG arrived in 1996 as a free replacement for the patent-encumbered GIF. It is lossless, supports transparency, and is excellent for graphics with sharp edges — screenshots, logos, line art, UI assets. It's terrible for photographs because it doesn't throw anything away: a 4K photograph as PNG is often five to ten times larger than the same image as JPEG.

WebP shipped in 2010 from Google, derived from the VP8 video codec. It supports both lossy and lossless modes, supports transparency in both, and at lossy settings produces files 25-35% smaller than JPEG at visually identical quality. Browser support is now universal — Safari was the holdout and shipped support in 2020.

AVIF shipped in 2019, derived from AV1 video. At low bitrates it's spectacular — typically 50% smaller than JPEG and 20% smaller than WebP at matched quality — and it supports 10-bit and 12-bit color, wide gamut, and HDR. The trade-off is encode time (much slower than JPEG or WebP) and the long tail of tools that still don't read it.

The same image in every format — real numbers

Here's a representative 4K landscape photograph (3840 x 2160, taken on a recent mirrorless camera) saved in each format at visually-equivalent quality. JPEG at Q85: 380 KB. PNG (lossless): 11.2 MB. WebP at Q85: 210 KB. AVIF at Q60 (roughly matched perceptual quality): 170 KB.

Now the same image with a flat colored region (a screenshot with text on a solid background). JPEG at Q85: 95 KB but with visible ringing around the text edges. PNG: 65 KB and perfect. WebP lossless: 48 KB. AVIF lossless: 41 KB. The pattern flips: for content with sharp edges, lossless formats win on both quality and size.

And a small icon (256 x 256, a logo with transparency). JPEG: not applicable (no alpha). PNG: 12 KB. WebP lossless: 7 KB. AVIF lossless: 6 KB.

The headline pattern across thousands of tests: AVIF wins on size at every quality level, WebP is close behind and much faster to encode, PNG wins for lossless graphics, and JPEG wins for compatibility above all else.

Browser and platform support in 2026

JPEG: every device built in the last 30 years. There's no support consideration.

PNG: same as JPEG for the common 8-bit case. PNG-16 (16-bit-per-channel HDR PNG) is more recent and not universal.

WebP: every modern browser since 2020. Email clients are more mixed — Gmail and Apple Mail render WebP inline, Outlook desktop sometimes does not. Save email attachments as JPG or PNG.

AVIF: Chrome, Edge, Firefox, Safari (since 16.4 / 2023). The remaining gaps are some older email clients, some image-processing services, and some corporate intranet tools that haven't updated. For anything user-facing on the open web, you can rely on AVIF; for anything that might pass through a long pipeline of unknown tools, JPEG is still safer.

The HEIC and iPhone-interop problem

HEIC (technically HEIF wrapping HEVC) is what iPhones save photos in by default since iOS 11. It's roughly comparable to AVIF in efficiency, but it's encumbered by patents and is genuinely awkward to open on non-Apple platforms. Windows requires a paid codec extension; Android phones can't open it without an app; most web tools refuse to upload it.

The practical answer is: keep HEIC for storage if you're an iPhone user (you save a lot of space), but convert to JPG or AVIF before sharing or uploading. SnapToolz Convert Image handles HEIC in the browser — it's one of the few tools that does — so you can drop an iPhone photo and get a JPG back without installing anything.

The decision tree

Publishing to the modern open web (your site, a blog, a portfolio)? Use AVIF with WebP fallback, JPEG as the final fallback. <picture> in HTML makes this one line of markup.
Need transparency (logo, icon, PNG-style asset)? Use PNG for compatibility, or WebP lossless / AVIF lossless if you control the consumer.
Sending in email or messaging? Use JPG. WebP and AVIF are still risky in older Outlook installs and some corporate filters.
Archiving photographs at the best quality / size ratio? AVIF for new archives, JPEG for ones you'll share around.
Working with an iPhone library? Keep HEIC at rest, convert to JPG/AVIF on export.
Targeting a printer or a print shop? Use JPEG or TIFF; many RIPs still don't accept WebP or AVIF.

Tools used in this guide

Run it as a workflow

Web-ready images
Convert to WebP, then compress to upload-friendly sizes. Built for landing pages and blog posts.

FAQ

Why does my WebP look worse than my JPEG at the same file size?: Almost always because the quality setting numbers don't map across formats. 'Quality 85' in JPEG and 'Quality 85' in WebP produce different bitrates. A same-size comparison can be unfair to WebP. SnapToolz Convert Image has a 'match quality' mode that uses perceptual-quality-matched encodes so the comparison is honest.
Should I just convert all my old JPEGs to AVIF to save space?: Probably not. Re-encoding a lossy format to another lossy format generationally loses quality (the second encoder sees the artifacts of the first as 'real detail' and tries to preserve them). You'll save some bytes but the per-byte quality goes down. AVIF is best applied to a high-quality source — the original RAW or PNG — not as a re-encode of an old JPEG.
Does AVIF support animation like GIF?: Yes — animated AVIF exists, with full color depth and alpha. File sizes are dramatically smaller than animated GIF (often 10x smaller for the same animation). Browser support for animated AVIF lags the still-image case slightly; on important surfaces you may still want an MP4 or WebM as the fallback for animation.
I exported a screenshot as JPEG and the text looks fuzzy — why?: JPEG's frequency-domain compression hates sharp edges. Text on a flat background is the worst case for it: every letter edge becomes a high-frequency component that the encoder either preserves at high bitrate or smears into ringing artifacts. Use PNG, WebP lossless, or AVIF lossless for screenshots of text.