PNG is beloved for two things: lossless quality and transparency. But those strengths come with a heavy cost in file size, especially for detailed or photographic images. A single PNG hero image or product cutout can weigh several megabytes, dragging down page load times. AVIF offers a way out: it keeps the transparency and visual quality you need while cutting the file size dramatically.
This guide explains how and why to convert PNG to AVIF for the web, how transparency is preserved, which quality settings to use, and how to serve the result safely with fallbacks. The browser-based PNG to AVIF tool does the conversion locally. Let us start with why PNGs are so large in the first place.
Why PNG Files Are So Large
PNG uses lossless compression, meaning it stores every pixel exactly with no detail discarded. That is perfect for fidelity, but it makes PNG inefficient for complex images. Photographs and richly detailed graphics have so much unique pixel data that lossless compression cannot shrink them much, leaving you with enormous files. PNG shines for simple graphics with flat colors but struggles with photographic content.
For the web, those large files are a liability. They consume bandwidth, slow down page loads, and hurt performance scores. AVIF solves this by using efficient, modern compression while still supporting the transparency that made you choose PNG. To understand the format, see what is an AVIF file.
How Much Smaller Will Your PNGs Get?
The savings can be dramatic. For photographic or detailed PNGs, AVIF often produces files a small fraction of the original size, sometimes 80 to 90 percent smaller, while looking visually identical. Even for simpler graphics, AVIF usually beats PNG comfortably. A multi-megabyte PNG can routinely shrink to a few hundred kilobytes or less.
Crucially, this happens without sacrificing transparency. AVIF supports a full alpha channel, so your transparent backgrounds, soft edges, and overlays survive the conversion intact. You get PNG's capabilities at a fraction of the weight.
Does PNG to AVIF Keep Transparency?
Yes. This is the key reason AVIF is a worthy replacement for PNG rather than just for JPEG. Because AVIF includes an alpha channel, transparent pixels stay transparent and anti-aliased edges remain clean. A transparent logo converted to AVIF will sit cleanly on any background, just as the PNG did, but in a far smaller file.
This is what separates AVIF from JPEG for this use case. If you converted a transparent PNG to JPEG, the transparency would be flattened to a solid color. AVIF avoids that entirely. For more on how transparency behaves across formats, see AVIF to PNG transparency.
Choosing Lossy or Lossless AVIF
AVIF offers both lossy and lossless modes, and the right choice depends on your content:
- Lossy AVIF at a high quality setting is best for photographic PNGs and detailed graphics, delivering the biggest size savings with no visible quality loss.
- Lossless AVIF preserves every pixel exactly, useful for graphics where absolute fidelity is required, though files are larger than lossy.
For most web use, lossy AVIF at a high quality setting hits the sweet spot: tiny files that look identical to the original. Reserve lossless for cases where pixel-perfect accuracy genuinely matters, such as precise UI assets.
How to Convert PNG to AVIF Step by Step
Here is the complete workflow:
- Open the converter. Go to the PNG to AVIF tool in your browser.
- Add your PNG files. Drag in one image or a whole batch.
- Choose lossy or lossless and a quality level. Lossy at high quality suits most web images.
- Convert. The tool encodes your AVIF files locally, preserving transparency.
- Download. Save the AVIF files, or the ZIP for a batch.
- Compare sizes. Check the reduction against your originals before deploying.
Because encoding AVIF is more intensive than PNG, a large batch may take a moment, but the file size payoff is worth it.
Serving PNG-Derived AVIF with Fallbacks
AVIF support is broad but not universal, so for transparent images you should serve a fallback. The HTML picture element handles this: offer AVIF first, then a WebP fallback (which also supports transparency), and finally the original PNG for any browser without modern format support. This guarantees transparent images display correctly everywhere.
- First source: the AVIF file, smallest and best for modern browsers.
- Second source: a WebP version with transparency for broader support.
- Final img tag: the original PNG as the universal fallback.
Our AVIF browser support guide explains exactly which browsers need the fallback, and the AVIF to WebP tool helps create the WebP layer.
PNG to AVIF vs JPG to AVIF: What's Different?
Both conversions move you to the efficient AVIF format, but they start from different places:
- PNG to AVIF is about shrinking heavy, often transparent images while keeping the alpha channel. The size savings are usually enormous.
- JPG to AVIF is about squeezing already-compressed photos a bit further, with savings of 30 to 50 percent and no transparency involved.
If your images have transparency, PNG to AVIF is the relevant path. For photographs, our JPG to AVIF guide covers that case. And whenever you need to reverse direction for compatibility, the AVIF to JPG tool produces a universally openable file.
Conclusion
Converting PNG to AVIF for the web gives you the best of both worlds: PNG's transparency and quality in a file a fraction of the size, often 80 to 90 percent smaller for detailed images. Use lossy AVIF at high quality for most images, serve it with a WebP and PNG fallback, and watch your pages load faster. Ready to slim down those heavy PNGs? Open the PNG to AVIF converter, drop in your files, and download tiny, transparent AVIFs. Explore the full avif.tools suite to convert in any direction.