Convert PNG to AVIF
AVIF usually lands a PNG somewhere between a fifth and a tenth of its original size, which is a bigger saving than any other format switch available on the web today. It is also lossy by default and unsupported in a few places that still matter, so this page is as much about when not to use it as how.
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Add to Chrome — freeDrop your PNG file here, or click to browse
Up to 50 MB. Deleted automatically after 30 minutes.
What it does
- Large size reduction at visually identical quality
- Alpha transparency carried across intact
- Wide color and 10-bit depth supported
- Honest about the encoding cost and browser gaps
How to use PNG to AVIF
- 1
Add the PNG
Screenshots, exported UI assets, logos and illustrations all work. Files with transparency are fine — AVIF carries an alpha channel, unlike JPEG, which is why it can replace PNG in places JPEG never could.
- 2
Leave the output as AVIF
Quality is set to a level where the difference from the source is not visible at normal viewing size. There is no slider here on purpose: per-image quality tuning belongs in an image editor, not a one-click converter that would invite guessing.
- 3
Convert, then check it in place
Download the result and view it where it will actually be used. AVIF's artifacts are different in kind from JPEG's — it smooths rather than blocks — so the way to judge it is on your own image, not on a comparison table.
How it works
The PNG is decoded and re-encoded with libaom, the reference AV1 encoder, using AV1's still-image profile. AVIF is not a new compression design so much as a video codec's intra-frame coding applied to a single picture — which is exactly why it is so much better than formats designed in the 1990s. Two decades of video research went into predicting what a block of pixels will look like, and a still image gets all of it.
The alpha channel is encoded as a separate monochrome plane alongside the color data, which is the mechanism that lets AVIF do what JPEG cannot: replace a PNG without flattening its transparency onto a background.
Where the saving actually comes from
AVIF is strongest on exactly the content PNG is weakest on. PNG compresses by finding repetition along scanlines, which works beautifully on a solid-color rectangle and poorly on a photograph, where almost no two adjacent pixels match. That is why a photographic PNG is enormous.
AVIF instead predicts each block from its neighbors and stores only the difference. Gradients, skin tones and out-of-focus backgrounds — all the things that defeat PNG — cost it very little.
The practical consequence is that the biggest wins come from files that should probably never have been PNG in the first place: photographs exported from a design tool, or screenshots of photographic content. A logo saved as PNG is already close to optimal and will barely move.
The encoding cost nobody mentions
AVIF is slow to encode. Compressing a large image can take several seconds of real CPU work, against a fraction of a second for PNG or JPEG. Decoding is fast, so this is invisible to whoever views the image later — but it is the reason this conversion runs on our server rather than in your browser, and the reason converting a large batch is not instant.
It is also worth knowing if you are considering AVIF for a build pipeline. The encode cost is paid once per image, so it is nearly always worth it for assets served repeatedly, and rarely worth it for something generated per request.
When to stay on PNG
Keep the PNG when the file is small, when it is a master copy you will edit again, when it is going into an email, or when it will be opened by software you do not control. Switch to AVIF when the image is large, photographic or screenshot-like, and headed for a modern browser — which is where the tenfold reductions in the examples above come from.
Examples
A UI screenshot with flat color
Roughly a tenth of the size. Screenshots are AVIF's best case: large areas of flat color and sharp text are what its prediction handles well. The same image as JPEG at comparable quality would land near 140 KB and would show ringing around the text.
A small logo with transparency
Barely a saving, and this is the case worth knowing about. AVIF carries a fixed container overhead of roughly a kilobyte, so on genuinely small files it wins little and can occasionally lose. Below about 10 KB, keeping the PNG is usually the better call.
Frequently asked questions
Is AVIF lossless like PNG?
It can be, but this converter does not use that mode. Lossless AVIF exists and beats PNG by around 20 percent, which is a real gain but nothing like the reduction people come to this page for. The lossy mode used here is where the dramatic numbers come from, and on photographs and screenshots the loss is not visible at normal viewing size.
Which browsers cannot display AVIF?
Every current desktop and mobile browser supports it, including Safari since version 16. What still fails is older software rather than the modern web: email clients are the common trap, several of which show a broken image, along with anything running a browser engine from before 2022 and a good deal of desktop image software.
Why did my file get bigger?
Almost always because the source was already very small. AVIF's container carries about a kilobyte of overhead before any image data, so a 3 KB icon has nothing to gain and something to lose. It can also happen on images with heavy film grain or dithering, where the noise is expensive to encode and PNG's compression handles the repetition better.
Should I keep the PNG originals?
Yes, if the PNG is your master copy. AVIF here is lossy, so converting back to PNG later returns the file to a lossless container without returning the discarded detail. Treat the AVIF as an output for delivery and keep the PNG as the source, the same way you would treat an export from a design tool.
Further reading
- Cutting a Graphic to Sixteen Colors Saved Fourteen Per CentReducing the palette is standard advice for shrinking a PNG, and on a graphic that is already flat color it buys far less than the drastic-sounding change suggests. The reason is that PNG was already exploiting the same redundancy, and it had got there first.
- Mono at 16 kHz Was a Fifth of Stereo, and at a Fixed Bitrate Nothing ChangedMaking a recording mono is the standard advice for shrinking speech audio, and whether it works depends entirely on a setting most people never touch. Set one way it saves eighty per cent; set the other way it saves nothing at all and quietly improves the quality instead.
- A PNG Logo Wins Up to 128 Pixels, and the SVG Wins Everywhere AboveA vector file costs the same whatever size it is drawn at, and a raster costs what its grid costs — so there is a size where one overtakes the other. On a logo it arrives sooner than most people assume, and the file-size argument is the least important half of the decision anyway.