What does the Image Format Analyzer do?

It reads your uploaded image entirely in your browser, extracts its format, dimensions, and file size, then re-encodes it at 80% quality in WebP and AVIF to estimate how much space you'd save by converting. No data ever leaves your device.

Why should I convert my images to WebP or AVIF?

WebP images are typically 25–35% smaller than JPG at the same visual quality. AVIF goes even further at 40–50% smaller. Smaller images mean faster websites, lower bandwidth costs, and better Google Core Web Vitals scores.

What image formats can the analyzer detect?

The analyzer supports JPG, PNG, WebP, AVIF, HEIC (iPhone photos), and JXL (JPEG XL). It detects the format from both the file extension and MIME type.

Why is the estimated size not shown for some formats?

Estimated sizes are calculated by re-encoding the image using your browser's Canvas API. Some formats — like AVIF — require a browser with encoding support (Chrome 85+, Firefox 93+). If your browser can't encode the format, a typical savings range is shown instead.

Is my image uploaded when I use this tool?

No. The Image Format Analyzer runs 100% in your browser. Your image is read directly by JavaScript and never sent to any server. This makes it safe for private or sensitive photos.

What is the best image format for the web?

For most web use, AVIF offers the best compression efficiency and is supported in Chrome, Firefox, and Safari 16+. WebP is the next best choice with broader compatibility. Use JPG or PNG only when maximum compatibility with older software is required.

How accurate are the size estimates?

The estimates are calculated by actually re-encoding your image in WebP or AVIF at 80% quality — the same operation that would happen during conversion. The real savings you get from using the converter tools may vary slightly based on the quality setting you choose.

Can I analyze multiple images?

Currently the analyzer works on one image at a time so you can review the detailed recommendation before converting. Use the Converter tools on this site for batch processing.

Image Format Analyzer — Find Best Format

What is an Image Format Analyzer?

An image format analyzer inspects an image file and tells you exactly what format it is, how large it is, and — most importantly — how much smaller it would be in a more efficient format. This helps you make an informed decision before converting, so you know precisely what you'll gain.

Why does image format matter?

Choosing the right image format can reduce file sizes by 30–70% with no visible quality difference. For websites, this directly translates to faster page loads, lower bandwidth costs, and better Google Core Web Vitals scores. For personal use, it means less storage consumed and faster uploads.

How does the analyzer estimate savings?

The analyzer loads your image into an HTML Canvas element — entirely in your browser, without any network request — and re-encodes it at 80% quality in WebP and AVIF. The resulting blob sizes are compared against your original file size to calculate exact savings percentages. This is the same process used by professional image optimization pipelines.

Which format should I use?

AVIF — Best compression. Supported in Chrome 85+, Firefox 93+, and Safari 16+. Ideal for web delivery.
WebP — Excellent compression with broader support. Recommended for any website targeting mixed browser versions.
JPG — Universal compatibility with all software, devices, and services. Best for photos shared outside a browser context.
PNG — Lossless, supports transparency. Best for screenshots, logos, and graphics where every pixel must be exact.

Best image format for web: a quick guide

For most websites in 2026, AVIF is the best choice for photographic content — it delivers the smallest file at a given quality level and is supported by over 90% of global browser traffic. WebP is the safe fallback for any browser that doesn't support AVIF. JPG and PNG remain necessary for compatibility with desktop software, print workflows, and email clients.

Frequently Asked Questions

Find the Best Format for Your Image