PNG to AVIF Converter

Why PNG to AVIF conversion is optimal for modern web

Converting PNG to AVIF is a transition from a classic lossless format to a modern standard that can work both with and without loss. The main advantage of this conversion is that AVIF fully preserves PNG transparency while creating files 2-5 times smaller. For web developers, this means the ability to use images with alpha channels without compromising load speed.

PNG (Portable Network Graphics) has been the standard for web graphics requiring transparency since 1996. The format provides lossless compression and full 8-bit alpha channel. However, these advantages come at a cost: PNG files with photographic content can weigh tens of times more than equivalent JPEGs, and even simple graphics take up more space than necessary.

AVIF (AV1 Image File Format) appeared in 2019 as a result of work by the Alliance for Open Media — a consortium including Google, Apple, Microsoft, Amazon, Netflix, Meta, and Mozilla. Based on the AV1 video codec, the format offers unprecedented compression efficiency with full transparency support. For PNG files with alpha channels, AVIF is the first real alternative capable of reducing size without losing functionality.

Unique advantages of PNG to AVIF conversion

Full transparency preservation

Unlike JPEG and many other formats, AVIF fully supports 8-bit alpha channel — exactly like PNG. During conversion, the following are preserved:

• Fully transparent areas — pixels with alpha=0 remain completely transparent
• Semi-transparent effects — smooth shadows, blurred edges, glass overlays
• Gradient transparency — transitions from transparent to opaque
• Anti-aliasing — smoothed object edges on transparent background

This is critical for logos, icons, UI elements, and any graphics that must overlay arbitrary backgrounds.

Two compression modes for different tasks

AVIF offers flexibility unavailable in PNG:

Lossy — reduces size by 70-90% from PNG with minimal visual artifacts. Ideal for:

• Photos on transparent background (clipped products)
• Complex illustrations with many colors
• Images where slight losses are acceptable

Lossless — preserves every pixel identical to original, while file is 20-40% smaller than PNG. Suitable for:

• Pixel art where every pixel matters
• Screenshots with text
• Technical graphics and diagrams
• Source files for further editing

Comparison with WebP

WebP also supports transparency, but AVIF surpasses it in efficiency:

For PNG files with transparency, AVIF provides 20-30% better compression than WebP.

Technical aspects of PNG to AVIF conversion

How transparency encoding works

PNG stores alpha channel as a separate data plane, compressed along with color channels by the DEFLATE algorithm. AVIF uses a fundamentally different approach:

1. Premultiplied alpha — color components are multiplied by transparency value before encoding. This improves compression quality of semi-transparent areas.

2. Auxiliary planes — alpha channel is encoded as an auxiliary plane with separate quality settings. You can preserve alpha losslessly while compressing color with losses.

3. Chroma subsampling — for opaque areas, chroma subsampling (as in video) is applied, further reducing size.

Quality parameter impact

The quality parameter in AVIF (1-100) affects the balance of size and visual quality:

For most PNG files, quality 75-85 provides optimal balance: size decreases 3-5 times, while visual losses are imperceptible.

Use cases for PNG→AVIF

Web development: icons and UI elements

Modern sites use hundreds of icons, buttons, and interface elements with transparency. PNG sprites and individual icons can occupy hundreds of kilobytes.

AVIF conversion provides:

• Icon-set size reduction by 60-80%
• Sharp edges and anti-aliasing preservation
• Faster interface loading

Example: set of 100 icons 64×64 pixels

• PNG: ~800 KB
• WebP: ~320 KB
• AVIF: ~180 KB

E-commerce: products on transparent background

Online stores often use clipped product photos for placement on any background. High-resolution PNG product files take up megabytes.

AVIF allows:

• Preserving quality clipping without halos
• Reducing product card size 4-6 times
• Speeding up catalog loading by 50-70%

Design: logos and branding

Logos must work on any background and maintain perfect quality. PNG is traditionally used for logos with transparency.

AVIF in lossless mode:

• Bit-perfect identity with original
• Size 25-40% smaller than PNG
• Wide color gamut support for brand colors

Real size reduction examples

Conversion results for typical PNG files with transparency:

Average savings is 70-75% of PNG size.

AVIF browser and software compatibility

Browser support (2025)

Global coverage: ~93% of users. For remaining 7%, fallback is necessary.

Graphics editors

Website performance optimization through PNG→AVIF

Impact on Core Web Vitals

Largest Contentful Paint (LCP) — main content loading time. Large PNG images are often the cause of poor LCP scores. Reducing file sizes by 60-80% through AVIF directly speeds up visual content loading.

First Input Delay (FID) — response time to user's first action. Smaller image sizes mean less browser load during parsing and rendering, freeing the main thread for user input processing.

Traffic savings for users

Switching from PNG to AVIF is especially valuable for mobile users with limited traffic or unstable connections. With average size reduction of 70%, an online store with 50 product images per catalog page saves users about two megabytes of traffic per page load.