JPG Vs. PNG Vs. WEBP Vs. AVIF: Guide To Choosing The Best Web Image Format

Imagine this: You've spent weeks designing your website—beautiful images, perfect layout, everything just right. But when you finally hit “publish,” your excitement fades. The site is painfully slow, and visitors are leaving before they even see your stunning work. What went wrong?

In fact, according to Google, the probability of bounce increases 32% as page load time goes from 1 second to 3 seconds.

The culprit: your images. They’re too large, dragging down your load times. Choosing the wrong image format can have this exact effect, frustrating users and hurting your SEO.

With so many options—JPG, PNG, WEBP, AVIF—how do you know which is right? 

In this post, we’ll help you unpack the best image format for your site, ensuring it looks amazing and loads quickly. Let’s dive in!

Understanding the Basics of Image Formats

JPG (JPEG)

JPEG (Joint Photographic Experts Group), commonly known as JPG, is one of the most widely used image formats. It's designed for photos and images with many colors. 

The format uses lossy compression, which means some image data is lost during compression, but it also drastically reduces file size.

• Strengths: JPEG is excellent for photographs and large images with lots of colors, widely supported across all browsers and devices.
• Weaknesses: Lossy compression means quality degrades with each save. Not ideal for images requiring transparency or sharp edges, like logos.

PNG

PNG (Portable Network Graphics) is a format designed for lossless compression, meaning no quality is lost when the image is compressed. 

It also supports transparency, making it ideal for web elements like logos and icons.

• Strengths: It is perfect for graphics, logos, and images that require transparency or sharp details. The quality remains intact even after multiple saves.
• Weaknesses: Larger file sizes compared to JPG, which can slow down page load times.

WEBP

WEBP is a modern image format developed by Google that provides both lossy and lossless compression. 

It offers much better compression than JPG and PNG while maintaining image quality. 

Google claims that WEBP can reduce image sizes by up to 34% compared to JPG and 26% compared to PNG.

• Strengths: WebP are smaller file sizes with minimal quality loss, supports both transparency (like PNG) and animation (like GIF).
• Weaknesses: Slightly less widespread browser support, although adoption is rapidly growing. Moreover, older versions of Internet Explorer and iOS Safari may not fully support it.

AVIF

AVIF (AV1 Image File Format) is the newest of the bunch, providing high compression efficiency with minimal quality loss. 

It’s based on the AV1 video codec and offers superior compression to both WEBP and JPG.

• Strengths: It provides up to 50% better compression than WEBP, with minimal quality loss. Supports transparency and HDR images.
• Weaknesses: Still relatively new, so browser support isn’t universal. Processing AVIF images requires more CPU power, which may affect load times on low-end devices.

Key Factors to Consider When Choosing the Best Format for Images

So which factors and aspects to consider when you are choosing the best web image format for your website? Let’s understand that. 

1. Compression Type (Lossy vs. Lossless)

Compression is a major factor in how images affect website performance.

• Lossy compression (used by JPG and WEBP) reduces file size by removing some data from the image, which can affect quality but drastically improves loading speed. For example, JPG uses lossy compression to reduce a 2MB image to around 500KB, making it faster to load.
• Lossless compression (used by PNG, WEBP, and AVIF) keeps all the image data intact but often results in larger files. PNG is commonly used for images where clarity and detail are critical, such as logos or text-heavy graphics.

When quality and details matter (for example, in logos or UI elements), a lossless format like PNG or AVIF may be ideal. 

However, for images where size is more critical than perfect quality (like blog post illustrations), lossy formats like JPG or WEBP are preferable.

2. Transparency Support

If your site design requires images with transparent backgrounds (like logos or icons), you need to choose a format that supports transparency.

• PNG and WEBP both offer transparency support, making them ideal for web design elements that must blend seamlessly with different backgrounds.
• JPG does not support transparency, so it’s not ideal for graphics or logos.

3. Browser & Device Compatibility

Ensuring that your images load properly across all browsers and devices is crucial for a smooth user experience.

• JPG and PNG are universally supported by all major browsers and devices.
• WEBP is supported by around 94% of browsers, including Chrome, Firefox, and Edge. However, older versions of Safari on iOS devices may not support it.
• AVIF support is steadily increasing but remains at around 74% as of 2024, with some older devices and browsers still lacking native support. However, major browsers like Chrome and Firefox have added AVIF support in recent updates.

4. File Size vs. Quality

The balance between file size and image quality is a delicate one, especially when optimizing for website speed. Smaller image file sizes help your site load faster, which improves SEO and user experience..

• JPG typically offers the best balance between file size and acceptable quality for photographs and large images.
• WEBP can reduce file sizes by up to 34% compared to JPG without sacrificing quality. For example, a 500KB JPG can be reduced to about 330KB as a WEBP image.
• AVIF offers even better compression, sometimes reducing the size by an additional 50% compared to WEBP. This can lead to an AVIF file being around 250KB, with almost no visible quality loss.

Must Read: Webflow Mobile Optimization Made Easy: Essential Tips & Tricks

When to Use Each Image Format: Practical Scenarios

In case it’s still not clear, I have shared possible use cases and practical scenarios where each image format can be used. 

JPG Image Format: Best for Photographs and High-Color Images

JPG excels when dealing with photographs, complex color gradients, and large images. 

Because of its high compression capabilities, it ensures faster load times for media-heavy websites like blogs, e-commerce sites, or photo galleries.

Use cases: Blog post images, large hero images, and social media graphics.

PNG Image Format: Best for Graphics, Logos, and Transparent Images

PNG should be your go-to format for images that need sharp edges, high clarity, and transparency. 

For example, if you’re designing a website that relies on clean, crisp logos or intricate UI elements, PNG’s lossless compression ensures the best quality.

Use cases: Logos, infographics, screenshots, and icons.

WEBP Image Format: A Modern Solution for Speed and Quality

WEBP strikes the best balance between file size and quality. It’s perfect for websites prioritizing speed without compromising on the quality of visuals.

Use cases: Responsive images for blogs, e-commerce product photos, and mobile-optimized content.

AVIF Image Format: The Next-Gen Format for High Quality and Compression

If you want the smallest possible file sizes while maintaining high image quality, AVIF is your best bet. It’s ideal for cutting-edge websites or apps aiming to reduce bandwidth without sacrificing visual fidelity.

Use cases: High-resolution images for apps, photography portfolios, and websites with large galleries.

Tools for Converting Image Files from JPG/PNG to WEBP or AVIF

1. Online Tools

• Convertio: Supports multiple formats like JPG, PNG, WEBP, and AVIF. It’s user-friendly and doesn’t require any software downloads.
• Squoosh: A free, browser-based tool by Google that allows you to compress and convert images to WEBP or AVIF, showing a live comparison of file size and image quality.
• CloudConvert: Great for batch conversions between formats, including WEBP and AVIF. It integrates with services like Google Drive or Dropbox.

2. Software & Plugins

• Adobe Photoshop: Allows exporting images to WEBP via plugins. You can also extend it to work with AVIF using third-party add-ons.
• GIMP: A free image editor that supports both WEBP and AVIF conversion, with the right extensions.
• ImageMagick: A command-line tool that can handle batch conversions of images to WEBP and AVIF, suitable for automating workflows.

3. WordPress Plugins

• ShortPixel and Imagify: Automatically convert uploaded images to WEBP and AVIF on the server side, optimizing your website's performance without manual intervention.

How to Optimize Your Images for the Web

Optimizing images for the web goes beyond choosing the right format. Here are some additional best practices:

• Responsive Images: Use the HTML srcset attribute to serve different image sizes based on the user’s device, ensuring mobile users don’t download unnecessarily large files.
• Lazy Loading: Delay loading images until they are needed (i.e., when the user scrolls to them). This can reduce initial load time significantly.

Must Read: How Webflow Reduces Bandwidth Consumption for Your Website

FAQs

1. What is the difference between lossy and lossless compression in image formats?

Lossy compression reduces the file size by permanently removing some image data, which can lower image quality. This is commonly used in formats like JPG and WEBP. 

Lossless compression, on the other hand, retains all image data, ensuring no quality is lost, and is used in formats like PNG and AVIF. Lossless formats tend to have larger file sizes compared to lossy formats.

2. Which image format is best for websites focused on speed?

For websites prioritizing speed, WEBP and AVIF are the best options. WEBP reduces image sizes by up to 34% compared to JPG, while AVIF can reduce sizes by an additional 50% over WEBP. 

Both formats offer high compression with minimal quality loss, improving website load times and user experience.

3. Can all browsers and devices display WEBP and AVIF images?

While support for both formats is growing, WEBP is supported by approximately 94% of browsers, including Chrome, Firefox, and newer versions of Safari. 

AVIF has slightly lower support, around 74%, but is rapidly gaining popularity. If browser compatibility is a concern, fallback options (like JPG or PNG) should be provided using the picture tag in HTML.

4. What image format should I use for logos or graphics with transparent backgrounds?

PNG and WEBP are the best formats for images requiring transparency. PNG is ideal when you need lossless quality, while WEBP offers transparency support with smaller file sizes. 

AVIF also supports transparency, but its browser support is less extensive compared to PNG and WEBP.

5. How can I convert my images to WEBP or AVIF?

You can convert images to WEBP or AVIF using tools like Squoosh, Convertio, or CloudConvert for quick online conversion. 

For more advanced users, tools like Adobe Photoshop (with plugins), GIMP, and ImageMagick can handle conversions. WordPress users can automate this process with plugins like ShortPixel or Imagify.

Conclusion

Choosing the right image format for your website is critical for balancing performance, quality, and user experience. JPG works well for photos, while PNG is ideal for logos and graphics. WEBP offers excellent compression with modern browser support, and AVIF is the future of high-quality, low-size web images.

Once you experiment with different formats, use the right tools for conversion, and implement best practices like responsive images and lazy loading, you can optimize your site's performance and improve user experience while boosting SEO.