How should front-end developers choose image formats? Now there's a brand-new answer!

In front-end development, the choice of image formats not only affects loading speed and page performance but also directly impacts user experience and bandwidth costs. Common past recommendations were:

Use JPEG for photo-like images, balancing quality and size;

Use PNG for transparent images or icons, prioritizing lossless clarity;

Use GIF or WebP for simple or lightweight animations;

Use SVG for icons and vector graphics, ensuring scalability without distortion.

But now, this list can be updated.

The New PNG Format Standard

On June 24, W3C officially released the PNG Third Edition Specification—the first major upgrade to the format since 2003, after 22 years. The new specification not only fixes existing issues but also introduces modern image requirements like HDR, high-quality animations, and Exif metadata, expanding PNG's applicability in front-end image processing once again.

New Features

HDR (High Dynamic Range) Support:As display technology evolves, HDR content is becoming increasingly common. The third edition of PNG introduces lightweight metadata blocks to natively support HDR images.

Advantages: Compared to JPEG, PNG retains richer highlight details and more realistic color gradations.

File Size Impact: Minimal, adding only 4–20 bytes without affecting the compression efficiency of the main image data.

Use Cases: Product renders, promotional illustrations, high-quality photography, and other images demanding high visual fidelity.

Official Animation Support (APNG):Although Mozilla proposed the APNG format as early as 2008, it wasn’t officially standardized until the third edition. APNG inherits PNG’s lossless compression, true color, and transparency advantages while adding frame animation capabilities.

Advantages: Far superior to GIF in quality, supporting 24-bit color and alpha transparency, ideal for high-fidelity UI animations.

File Size Impact: Depends on frame count and compression optimization; typically slightly larger than GIF but with higher visual quality. Frame-difference optimization can further reduce size.

Use Cases: Animated icons, frame-by-frame illustrations, modern emojis, button animations, etc.

Exif Metadata Embedding:PNG now supports embedding photographic metadata (Exif), including capture time, GPS coordinates, and device information, recorded in eXIf chunks. This aligns PNG with JPEG in image archiving and smart processing scenarios.

Advantages: No need to revert to JPEG to preserve shooting information in lossless images, better suited for professional workflows.

File Size Impact: Controllable, typically adding tens to hundreds of bytes.

Use Cases: Photo libraries, upload archives, AI image recognition, photo management, etc.

Impact on File Size

In other words:

For ordinary static images, PNG file size remains largely unchanged;

For scenarios requiring HDR or animation, you can freely choose whether to enable these features;

New features are incrementally compatible, allowing legacy projects to continue unchanged.

Ecosystem Support

The new standard has been widely adopted by platforms and software, including:

Browsers: Chrome, Safari, Firefox, and others already support the new features;

Operating Systems: Apple’s iOS and macOS natively support it;

Image Processing Software: Adobe Photoshop, DaVinci Resolve, and others are already compatible.

How to Choose Image Formats Now?

Considering the new PNG capabilities, here’s the recommended approach for selecting image formats in front-end development: