WebP vs JPEG vs PNG: Which Image Format Should You Use?

WebP vs JPEG vs PNG is a question with a straightforward answer in most cases: use JPEG for photographs, PNG for screenshots and images requiring lossless accuracy, and WebP for everything if your audience uses modern browsers. WebP averages 25-35% smaller than JPEG at equivalent quality and about 25% smaller than PNG for graphics. It supports both lossy and lossless compression and handles transparency. WebP is the default choice for any new web project.

That's the short version. The longer version matters because there are real situations where the default is wrong, and using the wrong format for a given image type can make files 3-5x larger than they need to be.

JPEG: Best for Photographs, Wrong for Screenshots

JPEG uses lossy compression, which means it discards information to achieve smaller files. The compression algorithm works by transforming image data into frequency components and discarding the high-frequency detail that human vision is least sensitive to. This works well on photographs and complex real-world imagery — continuous gradients, skin tones, foliage, anything where your eye naturally blends adjacent colors together.

It works poorly on flat-color areas, text, sharp geometric edges, and UI screenshots. Apply JPEG compression to a screenshot of a web interface or a logo and the artifacts appear immediately: ringing around high-contrast edges, blocky areas in what should be flat solid colors, blurring of text that should be sharp.

Quality settings for web use: 70-85% is the standard range. Going from quality 100% to 80% cuts file size by 50-60% with no perceptible degradation on typical monitor resolutions. The quality scale is not linear — the visible difference between 100% and 90% is smaller than the difference between 65% and 55%. Most of the perceptible quality loss happens below 65%.

A 1920×1080 photograph at JPEG quality 80% typically produces a file of 300-600KB, depending on image complexity. A low-detail image (blue sky, clean product photography) compresses smaller; a highly detailed image (crowd photo, forest) compresses larger.

One hard limitation: JPEG does not support transparency. Any JPEG placed over a colored background will have a white or colored box behind it. If you need transparency, JPEG is not an option.

There's also a compounding problem with JPEG editing: saving a JPEG multiple times reduces quality cumulatively. Each save is a lossy operation applied to the result of the previous lossy operation. If you're editing an image in multiple steps and saving JPEG between sessions, start from the original source file for the final export rather than recompressing the compressed version.

PNG: When You Need Pixel-Perfect Accuracy

PNG is lossless. The compression algorithm reduces file size by finding and encoding redundant patterns in the data, but no information is discarded. You can save a PNG file 1,000 times and the pixel values will be identical to the original on every save.

This makes PNG the correct choice for content where pixel accuracy matters: screenshots of code or interfaces, diagrams with text labels, icons, logos, images with flat color areas, and anything where you need to preserve sharp edges or exact color values.

PNG supports full transparency via an alpha channel. Each pixel can have any opacity from 0 (fully transparent) to 255 (fully opaque), which allows smooth semi-transparent edges and realistic shadows.

The cost is file size for photographic content. A 1920×1080 photograph saved as PNG runs 2-5MB. The same photograph as JPEG at quality 80% is 300-600KB. For photographs, PNG file sizes are 5-10x larger than JPEG with no visual benefit — the human eye can't distinguish lossless from lossy for photographic content at web viewing distances.

For graphics, logos, and screenshots, the math reverses. A logo that would be 50KB as JPEG (with visible artifacts around edges and color shifts in flat areas) might be 8KB as PNG — smaller, and with accurate rendering. PNG compression is effective on images with large uniform areas and repeating patterns.

PNG compression level affects encode time and file size, not quality. Running maximum compression on a PNG produces 10-20% smaller files than default compression. The decode time for the end user is not meaningfully affected.

WebP vs JPEG vs PNG: Why WebP Wins for Web Use

WebP was developed by Google and released in 2010. It supports both lossy compression (like JPEG) and lossless compression (like PNG), plus transparency in both modes. For most web use cases, it produces smaller files than either format at equivalent quality.

Browser support is universal: Chrome 23+, Firefox 65+, Safari 14+, Edge 18+. WebP is safe to use as the primary format for any new web project.

For photographs (lossy WebP vs JPEG): 25-35% smaller file size at equivalent perceived quality. A 1920×1080 photo that would be 400KB as JPEG quality 80% is typically 280-310KB as WebP at equivalent quality.

For graphics with transparency (lossless WebP vs PNG): approximately 25% smaller. The mechanism is different from PNG compression — WebP uses a different predictive coding approach that tends to find more redundancy.

WebP also supports animation, which replaces GIF with dramatically smaller files. An animated GIF that runs 2MB is typically under 300KB as animated WebP.

The weak points of WebP are worth knowing. Older tools don't always export to WebP natively — Photoshop required a separate plugin until CC 2022, and some image editing workflows default to JPEG or PNG. WebP is also less universally accepted as a file exchange format. If you're sending an image to a client for print or handing files off to a designer, JPEG or TIFF is still more appropriate. WebP is a web delivery format, not a working format.

AVIF: The Format Beyond WebP

AVIF (AV1 Image File Format) is the newest of the major web image formats. It's derived from the AV1 video codec and achieves compression that can be 50% smaller than JPEG in favorable cases. For certain image types, the quality-to-size ratio is substantially better than WebP.

Browser support is now broad: Chrome 85+, Firefox 93+, and Safari 16+ all support AVIF, and those versions have been current for years. The remaining friction is encoder speed and tooling. AVIF encoding is significantly slower than WebP encoding, which matters for automated image processing pipelines, and not all export workflows support it natively yet.

The right approach for most projects is to serve AVIF with a WebP fallback using the <picture> element — browsers that support AVIF use it, others fall through to WebP. For a single-format workflow where you want simplicity, WebP remains the easier default.

WebP vs JPEG vs PNG: Side-by-Side Comparison

Feature	JPEG	PNG	WebP	AVIF
Compression type	Lossy	Lossless	Lossy and lossless	Lossy and lossless
Transparency	No	Yes	Yes	Yes
File size (photograph)	Medium	Large	Small	Smallest
File size (logo / graphic)	Large	Small	Small	Small
Browser support	Universal	Universal	All modern browsers	All modern browsers
Animation	No	No	Yes	Yes
Multiple saves without quality loss	No	Yes	Yes (lossless mode)	Yes (lossless mode)
Best for	Photos without transparency	Screenshots, UI, transparency	General web use	Photos where file size matters most

Which Image Format Should You Use?

If you're targeting all modern browsers (the normal case): Use WebP for photographs and graphics alike. Use lossless WebP for content where pixel accuracy matters. Use PNG only if your tooling doesn't support WebP export or if the file will be used outside the browser context.

If you don't want to think about it: Use WebP for everything. The Image Converter handles the conversion in your browser with no uploads. If you have legacy tooling locked to JPEG and PNG, JPEG at quality 80% for photos and PNG for graphics is the fallback — but migrating to WebP is a one-time workflow change that immediately reduces your image file sizes by 25-35%.

For logos, icons, and geometric illustrations: Use SVG. An SVG is XML describing paths and shapes, scales infinitely, and is typically 2-20KB for a simple logo. If an icon or logo is geometrically defined, it shouldn't be a raster image format at all.

How to Convert Images to WebP, JPEG, or PNG

The conversion workflow is: open the source file, export to the target format with your chosen settings, verify visually at 100% zoom.

For batch conversion — say, converting a folder of product photos from JPEG to WebP before a site update — you need either an image editor that supports batch export (Photoshop, GIMP with batch export plugin, Affinity Photo) or a browser-based tool. The Image Converter for website uploads converts to WebP, JPEG, and PNG in your browser without uploading files to any server. Drag the file in, select format and quality, download the result.

The one thing to verify after any lossy conversion: open the output file in a browser at 100% zoom and look at the areas most likely to show artifacts — text within the image, high-contrast edges, flat-color regions. For photographs at quality 75-80%, you almost certainly won't see a difference from the original. For screenshots or UI captures, use lossless mode or PNG.

The format decision is upstream of compression settings in terms of impact. A PNG photograph is wrong before any quality settings come into play. A WebP graphic in lossless mode at 25% smaller than PNG is a better result than any amount of PNG compression tuning can achieve. Get the format right first, then tune quality settings.