Convert AVIF to transparent PNG — transparency preserved

Why convert AVIF to transparent PNG?

AVIF is a genuinely capable format for transparent imagery — it encodes alpha at high quality with file sizes that undercut PNG considerably. The problem is tooling support outside the browser. Adobe Illustrator before CC 2024 cannot import AVIF at all, which means any logo or vector export you receive as a transparent AVIF is immediately unusable in the most common professional illustration workflow. Sketch has no native AVIF decoder. Older Figma desktop builds require a plugin workaround. Print RIPs and PDF preflight engines — the software that validates files before they go to press — universally expect TIFF or PNG for transparent assets; AVIF is simply not in their vocabulary. CMS and DAM systems present a similar wall. Contentful, Sanity, and most headless CMS platforms accept AVIF for web delivery, but their image transformation pipelines do not always expose transparent AVIF to downstream integrations that request PNG. Legacy DAMs often store and serve the exact file you uploaded; if your marketing team needs a transparent asset for a PowerPoint deck or an email campaign tool that only imports PNG, the AVIF will silently fail or lose its transparency. Converting to PNG removes the uncertainty: a transparent PNG opens everywhere, requires no plugins, and survives every handoff.

What you lose and what you gain

PNG is a lossless format by design, which means the conversion from AVIF to PNG can only preserve information — it cannot lose more than the AVIF decoder itself already decided. Once libavif decodes the AVIF into a raw RGBA pixel buffer, every alpha value is an exact integer between 0 and 255. oxiPNG takes that buffer and writes the alpha bytes directly into the PNG file without any thresholding, quantization, or compositing step. A pixel that is alpha 180 in the AVIF source will be alpha 180 in the PNG output. If the original AVIF was encoded with lossy compression — which is common, since lossy AVIF at quality 85–90 delivers excellent results at compact sizes — those lossy artefacts are already baked into the decoded pixel values. The PNG cannot undo them; it simply records what the decoder produced. For transparent logos and UI assets this rarely matters: most are encoded losslessly or at very high quality specifically to avoid visible compression artefacts near transparent edges. The practical trade-off is file size. A 1024×1024 transparent logo that sits at roughly 52 KB as a lossy AVIF will expand to around 280 KB as an optimized PNG. AVIF's AV1-based compression is simply more efficient than PNG's DEFLATE for this class of content. That gap is real for web delivery, but irrelevant the moment the destination is a design tool, a print workflow, or any system that requires PNG specifically.

How to convert AVIF to transparent PNG

The conversion runs entirely inside your browser using WebAssembly. Your transparent AVIF never leaves your device — there is no upload, no server-side processing, and no account required:

1. Click "Convert to PNG →" above, or drag your transparent AVIF file directly onto the drop zone on the homepage. Both entry points route to the same local conversion engine.
2. The tool decodes your AVIF using libavif — the reference implementation from the Alliance for Open Media (github.com/AOMediaCodec/libavif), compiled to WebAssembly. libavif unpacks the AV1-coded image data and produces a raw RGBA pixel buffer. Crucially, it decodes the alpha plane in full: every transparent pixel, every semi-transparent edge, and every partially opaque gradient is represented as an exact 8-bit alpha value in that buffer.
3. The RGBA buffer — alpha channel completely intact — is passed to oxiPNG (github.com/shssoichiro/oxipng), a Rust-based PNG encoder compiled to WebAssembly. oxiPNG writes a standard RGBA PNG file. It applies lossless DEFLATE optimization to reduce file size, but it does not touch the pixel values themselves. The alpha data that came out of libavif goes straight into the PNG byte stream.
4. Click the download button. Your transparent PNG saves to the Downloads folder with the original filename and a .png extension. Open it in Illustrator, Figma, Photoshop, a browser tab, or a file preview — the transparent regions will appear transparent because the alpha channel is there, unchanged.
5. For the smallest possible PNG without sacrificing any alpha fidelity, open /convert and raise the oxiPNG optimization level to 6. Higher levels run more exhaustive DEFLATE search passes, which can trim 10–15% off the file size. The alpha channel is bit-for-bit identical at every optimization level.

File size comparison: transparent AVIF vs transparent PNG

Measurements from representative transparent-asset scenarios. AVIF sources were encoded at quality 90 using libavif with default alpha settings. PNG output used oxiPNG at optimization level 6.

When AVIF with alpha makes sense, and when PNG wins

Browser support for AVIF transparency is broad and mature. Chrome 85 and later, Firefox 93 and later, and Safari 16 and later all decode AVIF alpha correctly — which together covers essentially every browser actively in use in 2025. If you are delivering a transparent asset through a web pipeline where you control the output — a modern website, a Jamstack deploy, a CDN that serves correct MIME types — transparent AVIF is the rational choice. The file-size advantage at equivalent visual quality is not marginal; it is typically 4:1 to 6:1 over an optimized transparent PNG. PNG wins everywhere the recipient is a system rather than a browser. The diagnostic question is: will a human with a modern browser view this file, or will a piece of software process it? Software — a print RIP, a design application, an InDesign template link, a Python script using Pillow, a Zapier workflow that attaches images to emails — almost universally expects PNG for transparent content. Adobe Illustrator pre-CC2024 has no AVIF import at all. Sketch (any version before late 2024) silently strips transparency when it encounters AVIF. Microsoft Office applications on Windows do not render AVIF inline. Email clients — Gmail, Outlook, Apple Mail, and every major mobile client — do not support AVIF; a transparent PNG renders correctly in all of them. The AVIF-versus-PNG decision for transparency is therefore straightforward: AVIF for browser delivery, PNG for everything else.

Under the hood: which codecs are used

AVIF decoding is handled by libavif, the reference implementation maintained by the Alliance for Open Media at github.com/AOMediaCodec/libavif. libavif wraps libaom — the same AV1 codec that ships inside Chrome and Firefox — but adds the AVIF container layer that handles still images, animation, and alpha planes specifically. When libavif encounters a file with an alpha channel, it decodes both the primary image plane and the auxiliary alpha plane and assembles a unified RGBA pixel buffer. The alpha plane in AVIF is encoded as a separate monochrome AV1 image, which means it can be lossy or lossless independently of the color image; libavif decodes whichever mode the encoder chose and produces exact integer alpha values. PNG encoding is handled by oxiPNG at github.com/shssoichiro/oxipng, a Rust rewrite of OptiPNG. oxiPNG applies filter-type selection and multi-pass DEFLATE to minimize file size without altering any pixel values. The alpha channel byte sequence that libavif wrote into the RGBA buffer is copied verbatim into the PNG IDAT chunk. Both libavif and oxiPNG run inside a Web Worker, so the main browser thread stays responsive during decode and encode. No pixels leave your device at any point.