Every time you save an image, you choose a format — often without thinking about it. Most of the time the default works. But choose the wrong format and you can end up with a logo that has an ugly white box around it, a website that loads slowly because of oversized images, or a screenshot where the text looks smudged.
The three formats you'll meet most often are JPG, PNG and WebP. Each was designed for a different purpose, and each has clear strengths and weaknesses. This guide explains how they differ, gives you simple rules for choosing, and shows you how to convert between them when you need to.
The short answer
If you only remember one thing:
- Use JPG for photographs you want to share, send or print.
- Use PNG for logos, icons, screenshots and graphics with text, and anything that needs transparency.
- Use WebP for images on your own website, where smaller files mean faster pages.
The rest of this article explains why — and the exceptions.
How image compression works
To understand the formats, it helps to know the two kinds of compression.
Lossless compression makes a file smaller without throwing any information away. When the image is opened, every pixel is exactly the same as before. It works like a ZIP file for pictures.
Lossy compression makes a file much smaller by discarding detail that the human eye is unlikely to notice — tiny variations in color and texture. You choose how much to discard with a quality setting. At high quality the change is invisible; at low quality you'll see blurring and blocky patches, called artifacts.
Photos contain millions of subtly different colors, so lossless compression can't shrink them much, while lossy compression shrinks them dramatically. Graphics with large flat areas of color compress very well losslessly, and lossy compression tends to produce visible smudges around their sharp edges.
JPG (JPEG): the format for photos
JPG — also written JPEG — has been the standard format for photographs for decades. Almost every camera and phone saves photos as JPG by default, and practically every device, program and website can open it.
Strengths
- Very small files for photos, with adjustable quality.
- Universal compatibility: e-mail, printers, social networks, office software, official upload forms.
Weaknesses
- Lossy only. Each time you edit and re-save a JPG, a little more quality is lost.
- No transparency. Transparent areas must be filled with a solid color.
- Sharp edges and text can show fuzzy "halos", which is why screenshots saved as JPG often look slightly dirty.
Use JPG for: photos to share or print, pictures of people, places and products, and any image that needs to open everywhere.
PNG: the format for graphics and transparency
PNG was created as a lossless format for graphics. It keeps every pixel exactly as it is, and it supports transparency — including smooth, partial transparency for soft shadows and anti-aliased edges.
Strengths
- Lossless: perfect for images you'll edit repeatedly.
- Full transparency support, so logos sit cleanly on any background.
- Crisp text and sharp edges, ideal for screenshots, diagrams and interface designs.
Weaknesses
- Large files for photos. A photograph saved as PNG is often several times larger than the same photo as a good-quality JPG.
Use PNG for: logos, icons, illustrations with flat colors, screenshots, charts, and any image that needs a transparent background.
WebP: the modern all-rounder
WebP is a newer format developed by Google specifically for the web. It combines the abilities of both older formats: it supports lossy compression like JPG, lossless compression like PNG, transparency in both modes, and even animation.
Its main advantage is efficiency. According to Google's WebP documentation, WebP images are typically noticeably smaller than comparable JPG and PNG files at similar visual quality. Smaller images mean faster page loads, which matters for visitors on mobile connections.
Strengths
- Smaller files than JPG or PNG for comparable quality in most cases.
- Supports transparency and animation.
- Displayed by all current major web browsers.
Weaknesses
- Less universal outside the browser. Some older image editors, office programs, printers and upload forms still don't accept WebP.
- People downloading a WebP image may find it harder to open or edit on older devices.
Use WebP for: images published on websites and web apps, especially large photos and banners.
Side-by-side comparison
| Feature | JPG | PNG | WebP |
|---|---|---|---|
| Compression | Lossy | Lossless | Lossy or lossless |
| Transparency | No | Yes | Yes |
| Animation | No | No (standard PNG) | Yes |
| Typical size for photos | Small | Large | Smallest |
| Best for | Photos | Graphics, screenshots, logos | Website images |
| Compatibility | Universal | Universal | All modern browsers; varies elsewhere |
Which format for which job?
A photo to send by e-mail or messaging: JPG. It's small and everyone can open it.
A company logo: PNG with a transparent background, so it works on white, colored and dark backgrounds. For use on your website, a WebP version can be smaller.
A screenshot for a tutorial or support request: PNG. Text stays crisp and readable.
Product photos for an online shop: WebP on the website for speed, while keeping the original JPGs as your master copies.
An image to print: JPG at high quality, or PNG for graphics. Check what your print service accepts — many don't accept WebP.
An upload to an official form or job portal: use exactly the format the form requests. When in doubt, JPG for photos and PDF for documents.
How to convert between formats
RIZONI TOOLS converters run in your browser, so your images are processed on your own device and are not uploaded to our servers.
- The Image Converter converts between JPG, PNG and WebP in one place, with several images at a time.
- PNG to JPG lets you choose the background color used for transparent areas.
- JPG to PNG is useful when a program or editor requires PNG.
- The WebP Converter turns images into WebP for your website, or WebP images back into JPG or PNG for wider compatibility.
Common mistakes to avoid
- Saving screenshots as JPG. Text gets fuzzy edges. Use PNG.
- Saving photos as PNG for the web. The files are needlessly large. Use JPG or WebP.
- Converting JPG to PNG to "improve quality". Detail that JPG compression removed can't be brought back; the file just gets bigger.
- Re-saving JPGs again and again. Each save loses a little more quality. Keep an original and export copies from it.
- Forgetting about transparency. Converting a transparent PNG logo to JPG fills the background with a solid color. Choose that color deliberately.
- Sending WebP files to people who can't open them. For attachments and uploads, JPG and PNG are safer.
Related RIZONI TOOLS
- Image Converter — convert between JPG, PNG and WebP.
- Image Compressor — make images smaller in their current or a new format.
- PNG to JPG and JPG to PNG — quick one-way conversions.
- WebP Converter — create or convert WebP images.
Conclusion
There's no single "best" image format — only the best format for the job. JPG remains the universal choice for photos, PNG is essential for graphics, screenshots and transparency, and WebP is the efficient option for images on the web. Keep high-quality originals, export the format each situation needs, and your images will look good, load quickly and open wherever they're sent.