WebP vs JPG vs AVIF

For most people the answer is WebP: it is roughly 25 to 35 percent smaller than JPG at the same visual quality and every current browser reads it. Reach for JPG when a file has to open literally anywhere, and for AVIF when you want the smallest possible file and do not mind a slower encode.

Those three formats all store the same kind of thing — a photograph, compressed with loss you are not meant to notice. What separates them is how modern the compression is, and that modernity costs you in either browser support or encoding time. This post is about making that trade on purpose.

The one-line summary

If you read nothing else, read that table. The rest of this post explains where each number comes from and when the exceptions bite.

JPG: the format that opens everywhere

JPEG has been the default photo format since the 1990s, and that longevity is its whole value proposition. There is no device, no app, no ancient printer driver, and no email client that cannot open a JPG. If you are attaching a photo for someone whose software you cannot see, JPG removes all risk.

The cost is efficiency. JPEG compresses in 8 by 8 blocks and, by default, throws away colour detail through 4:2:0 chroma subsampling — it keeps full brightness information but stores colour at half resolution. For a landscape that is invisible. For red text on a white background it shows up as a smeared pink halo, which is why a screenshot full of text should never be a JPG.

If you have a folder of WebP or AVIF files and a program that will not open them, converting back to JPG is the reliable escape hatch. The WebP to JPG and AVIF to JPG tools do exactly that in your browser.

WebP: the sensible default

WebP is the format to reach for when you control where the image will be used. It gives you a 25 to 35 percent smaller file than JPG at the same perceived quality, it supports transparency like a PNG, and — the deciding factor — every browser in current use displays it. There is no longer a compatibility reason to avoid it on the web.

WebP also has two modes. Lossy WebP competes with JPG for photos. Lossless WebP competes with PNG for logos and screenshots, and usually wins. That flexibility means one format can replace both of the old ones for most websites.

• Use lossy WebP for photographs and hero images where a little loss is fine.
• Use lossless WebP for logos, icons, and screenshots with sharp edges and flat colour.
• Keep the transparency you had — WebP carries an alpha channel, so converting a transparent PNG loses nothing there.

The most common move is converting existing JPGs to trim page weight. The JPG to WebP tool does it in batches, and PNG to WebP handles your transparent graphics.

AVIF: smallest files, slowest to make

AVIF is the newest of the three and the most efficient. It comes from the AV1 video codec, and it can hold roughly half the file size of a JPG at the same quality — better than WebP, especially in smooth gradients like skies where older formats show banding. On paper it wins.

The catch is encode speed. Producing a good AVIF is computationally heavy and can take several seconds per image where JPG is instant and WebP is quick. For a single hero image that is a fine trade. For a batch of two hundred photos you will feel every second. There is also the support edge: AVIF works in Chrome, Firefox and Edge, and in Safari from version 16.4 onward, so a small slice of older Apple devices still cannot see it.

Because a few programs and platforms still reject AVIF on upload, keep a converter handy. The AVIF to JPG tool turns modern files back into ones anything can open.

How to actually choose

Forget the codec theory and answer one question: who opens this file, and do you control their software?

1. 1Sending to a person or an unknown system? Use JPG. It never fails to open.
2. 2Putting it on your own website or app? Use WebP. Smaller, universal in browsers, keeps transparency.
3. 3Optimising a few important images and speed is not a concern? Use AVIF for the smallest result.
4. 4Handling hundreds of files at once? Use WebP so the batch finishes this decade.

A note on lossless conversion between these formats: going from JPG to WebP or AVIF does not repair the loss the JPG already baked in. It only re-packages the pixels more efficiently. You can make a file smaller, but you cannot recover detail that JPEG already discarded.

Newer formats do not undo old damage. They only stop you adding more while spending fewer bytes.

The size gap is easiest to see on one image exported three ways at matched perceived quality:

sky.jpg    quality 82   ->  820 KB   (baseline)
sky.webp   quality 80   ->  560 KB   (~32% smaller)
sky.avif   quality 55   ->  410 KB   (~50% smaller, slow encode)

What about PNG and GIF?

PNG and GIF are not really rivals to these three. PNG is lossless and excellent for graphics with sharp edges, but far too heavy for photos. GIF is an animation relic with a 256-colour ceiling. WebP and AVIF both beat GIF for animation and beat PNG for size, which is one more reason they are worth adopting. If you need a specific pairing, the general image converter moves between all of them in one place.

Setting quality when you convert

All three formats have a quality dial, and the same instinct applies to each: the useful range is narrower than the slider suggests. Pushing quality to 100 rarely looks better than 90 and can double the file. Dropping below the comfortable band introduces artefacts before it saves much. Sensible starting points:

• JPG: quality 80 for general use, up to 85 for images with fine detail.
• WebP: quality 78 to 82 usually matches an equivalent JPG at a smaller size.
• AVIF: it holds quality at lower numbers than the others, so a lower setting still looks clean.

One habit saves you grief across all of them: keep the original. Once you have exported a lossy file, that is the most quality it will ever have. If you might need a different size or format later, go back to the source rather than converting the converted copy.

Quick answers

Is WebP always smaller than JPG?

Almost always at equal quality, by roughly a quarter to a third. On very small images the difference shrinks because format overhead becomes a bigger share of a tiny file.

Will AVIF replace WebP?

Not soon. AVIF is more efficient but slower to encode and slightly less supported, so both will coexist. Pick per job rather than betting on one winner.

Are these conversions private?

On Pixora, yes. Encoding and decoding for all three formats runs in your browser through built-in codecs, so your images are never uploaded to a server.