JPEG vs PNG vs WebP: Choosing the Right Image Format

Picking the wrong image format is one of the easiest ways to end up with files that are bigger than they need to be, or quality that is worse than it should be. JPEG, PNG, and WebP each have their strengths. Knowing when to use each one saves you time and produces better results.

This guide breaks down how each format works, what it is best at, and when you should reach for it. If you want a deeper look at the compression techniques behind these formats, check out our guide on how image compression works.

JPEG: Best for Photographs

JPEG has been the standard format for photographs since the early 1990s, and it is still one of the most practical choices today. It uses lossy compression, which means it discards some image data to produce smaller files. For photographs, this works extremely well because the human eye is not great at detecting the specific kinds of detail that JPEG removes.

A JPEG photo at 80 to 85% quality looks nearly identical to the original but can be three to five times smaller. At 60 to 70% quality, the file gets even smaller and still looks good for most uses, like uploading to a website or attaching to a form.

When JPEG Works Well

• Photographs with lots of color variation and natural scenes
• Portrait photos, including passport and ID images
• Scanned documents that contain photos
• Any image where small file size matters more than perfect accuracy

JPEG Limitations

JPEG does not support transparency. If you need a background-free image, JPEG is not the right choice. It also tends to look bad on images with sharp edges and flat colors, like logos or text screenshots, because the compression creates blurry artifacts around those sharp lines.

Another thing to keep in mind: every time you open a JPEG and save it again, the compression applies again and you lose a little more quality. Keep original files in a lossless format if you plan to edit them repeatedly.

PNG: Best for Graphics and Screenshots

PNG uses lossless compression. Every pixel in a PNG is stored exactly as it was in the original, and the file can be opened and saved as many times as you want without any quality loss. This makes PNG the go-to format for images where accuracy matters.

PNG also supports transparency, including semi-transparent pixels. This is essential for logos, icons, and any graphic that needs to sit on top of a different background.

When PNG Works Well

• Logos and brand graphics with flat colors
• Screenshots, especially ones with text
• Icons and interface elements
• Any image that needs a transparent background
• Images that will be edited multiple times before final delivery

PNG Limitations

PNG files are larger than JPEG files for the same photograph. If you save a photo as a PNG, you get perfect quality but a much bigger file. For photos that do not need transparency or repeated editing, JPEG is the more practical choice.

WebP: The Modern Alternative

WebP is a format developed by Google and released in 2010. It supports both lossy and lossless compression, and it supports transparency. In most cases, a WebP file is 25 to 35% smaller than an equivalent JPEG or PNG while maintaining the same visual quality.

WebP is now supported by all major browsers including Chrome, Firefox, Safari, and Edge. If you are building a website and want the best combination of quality and small file sizes, WebP is worth considering.

When WebP Works Well

• Web images where page load speed matters
• Cases where you want JPEG quality in a smaller file
• Replacing PNG graphics that do not need maximum compatibility
• Any situation where you can use a modern format and browser support is not a concern

WebP Limitations

Not every app or service accepts WebP. Government portals, older email clients, and some image editing tools may not handle WebP correctly. If you are uploading to a form that specifies JPEG or PNG, stick with those formats. WebP also has less support in image editing software compared to the older formats.

Comparison Table

Which Format Should You Use?

Here is a simple way to decide:

• Is it a photograph or a scanned document? Use JPEG.
• Does it need a transparent background? Use PNG or WebP.
• Is it a logo, icon, or screenshot with text? Use PNG.
• Is it going on a website and file size is critical? Use WebP if the platform supports it, otherwise JPEG for photos and PNG for graphics.
• Are you uploading to a government form or official portal? Use JPEG unless they specify otherwise.

How MB2kB Handles Each Format

MB2kB works with JPEG, PNG, WebP, and other common image formats. When you upload any image, the tool converts it to JPEG during compression to achieve the target file size. This makes it especially useful for situations where you need to hit a specific size limit, like 50 KB or 100 KB, for form uploads.

All processing happens in your browser. Nothing is sent to any server. The browser's Canvas API handles the conversion and compression, which means your images stay on your device throughout the process.

For more on picking the right format for web use, take a look at our guide on best image formats for web performance.