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

By : Safdar Waraich | Last updated: 31 Oct 2026

Images make a page more interesting, but they are also usually the heaviest part of it. A single photo straight from a phone can be several megabytes, while the text on the same page might be only a few kilobytes. If your images are too big, the page loads slowly, visitors wait, and some of them leave before they see anything.

One of the easiest ways to fix this is to choose the right image format. The three formats you will meet most often are JPG, PNG and WebP. They look similar on the screen, but they work in different ways, and each one is best at something different.

In this guide you will learn how each format works, what the differences mean in practice, which format to pick for photos, logos and screenshots, how to use WebP safely, and which mistakes to avoid.

The quick answer

If you are in a hurry, this table covers most situations:

Now let us see why.

Two ideas you need first: pixels and compression

A digital image is a grid of tiny coloured dots called pixels. A photo that is 4000 pixels wide and 3000 pixels high contains 12 million of them. If every pixel were stored in full, the file would be huge: at three bytes per pixel, about 36 megabytes. Image formats shrink that by compressing the data, and there are two kinds:

• Lossless compression makes the file smaller without throwing anything away. When you open the file, you get exactly the same pixels back. It is like packing a suitcase more neatly.
• Lossy compression makes the file much smaller by discarding details that the eye is unlikely to notice, such as tiny colour differences and very fine textures. It is like leaving some clothes at home to save space. You cannot get the discarded detail back.

This one difference explains most of what follows.

JPG (JPEG)

JPG and JPEG are the same format. It was designed for photographs and has been the standard for them for decades.

How it works: JPG uses lossy compression. You can usually choose a quality level. A higher level keeps more detail and makes a bigger file, and a lower level makes a smaller file with more visible damage.

Strengths

• Small files for photos and images with smooth gradients.
• Supported by every browser, phone, camera, editor and upload form.
• You can adjust quality to balance size and appearance.

Weaknesses

• No transparency. A JPG always has a solid background.
• Sharp edges and small text can look blurry or show faint “noise” around them.
• Every time you edit and save a JPG again, it loses a little more quality.

Use it for: photographs, blog images, product photos, and any case where you need a file that works everywhere.

PNG

PNG was created as a free, lossless alternative to older formats.

How it works: PNG uses lossless compression, so the image is stored exactly as it is. It also supports transparency, including soft, partly see-through edges, which makes it ideal for placing a logo on any background.

Strengths

• No loss of quality, even after repeated saves.
• Supports transparent and semi-transparent areas.
• Sharp lines, text and flat colours look clean.

Weaknesses

• Photographs saved as PNG are often much larger than JPGs, because photos contain a lot of fine variation that lossless compression cannot shrink much.
• It does not support animation in the standard form.

Use it for: logos, icons, screenshots, diagrams, charts, and images that need a transparent background.

WebP

WebP is a modern format developed by Google and first released in 2010. It combines most of the strengths of the other two.

How it works: WebP can use lossy compression (like JPG) or lossless compression (like PNG), and it supports transparency in both modes. It can also store simple animations. Google has reported that lossy WebP files are typically about a quarter to a third smaller than comparable JPGs, and lossless WebP files are typically smaller than comparable PNGs. The actual saving depends on the picture.

Strengths

• Usually the smallest files at similar visual quality.
• Transparency, even with lossy compression, which JPG cannot do.
• Supported by all current major browsers.

Weaknesses

• Older software, some image editors, some email programs and some upload forms do not accept it.
• When you save an image from a web page, you may get a WebP file that your other programs cannot open.

Use it for: website images where speed matters, ideally with a JPG or PNG fallback for places that need one.

A short note on other formats

• GIF is limited to 256 colours but supports simple animation. For anything beyond a small animation, a short video or an animated WebP is usually lighter.
• SVG is a vector format. It stores shapes and lines as instructions, not pixels, so it stays sharp at any size. It is excellent for logos and icons made of simple shapes, but it is not for photographs.
• AVIF is a newer format that can be even smaller than WebP. Browser support is good but not as universal, and not every tool can create it yet. Check the current support before you rely on it.

Side-by-side comparison

What the difference looks like in file size

Here is a realistic picture of how one photo can behave in the three formats. The numbers below are illustrative (they vary a lot from image to image), for a photo of 1200 × 800 pixels:

The PNG is about ten times larger than the JPG, and the WebP is smaller again. For a page with ten photos, that difference decides whether the page loads in a second or in several seconds.

Why transparency changes the choice

Imagine a logo with a transparent background. If you save it as PNG or WebP, it sits cleanly on a white page, a dark page or a coloured banner. If you save it as JPG, the transparent area has to be filled with a solid colour, usually white, so you get a white box around the logo. On a white page you may not notice, but on any other background the box is obvious.

The reverse matters too. If you convert a PNG with transparency to JPG, the transparent areas become solid. Our PNG to JPG Converter fills them with a background colour for exactly this reason. Keep your transparent original.

Size in pixels matters more than the format

A smaller file is not only about the format. The dimensions of the image matter just as much. A photo of 4000 × 3000 pixels shown in a space that is 800 pixels wide wastes a large amount of data, because the browser downloads the full image and then shrinks it on screen.

A good rule: make the image about as wide as the space where it will appear (or up to twice as wide for sharp results on high-density screens). For a blog article with a content width of 800 pixels, an image 800 to 1,200 pixels wide is usually plenty.

Resize first, then choose the format. The Image Resizer changes the dimensions and keeps the proportions, so the picture does not get stretched. Then use the Image Converter to save it in the format you want.

What quality setting should I use?

For lossy formats (JPG and lossy WebP), quality is usually a number from 1 to 100.

A setting of about 80 is a sensible starting point. Always compare the result with the original at full size before you publish, and look at the edges, the text and the dark areas where problems show up first.

How to use WebP safely

All current major browsers support WebP, so you can use it on a website with confidence. But a few places still need JPG or PNG: older software, some email programs, some marketplaces and forms. To be safe, you can offer both with the <picture> element:

<picture>
  <source srcset="photo.webp" type="image/webp">
  <img src="photo.jpg" alt="A clear description of the photo" width="1200" height="800">
</picture>

The browser picks the WebP version if it can, and otherwise falls back to the JPG. Keep a JPG or PNG copy of important images for uploads and sharing. If you receive a WebP file that another program will not open, convert it with the WebP to JPG Converter.

Some content management systems and plugins create WebP versions automatically. Check how yours works, so that you do not end up with two copies of every image or broken links.

Page speed: other image habits that help

• Lazy loading. Add loading="lazy" to images that are below the first screen, so that the browser downloads them only when the visitor scrolls near them. Do not lazy-load the main image at the top of the page, because that one should load first.
• Set width and height. Adding the width and height attributes lets the browser reserve the space, so the text does not jump around as images load.
• Avoid decorative bulk. Every image should have a purpose. Remove images that do not help the reader.
• Reuse and cache. Use the same image file where you can, so that visitors’ browsers can reuse it.

Faster pages are better for visitors, and Google includes loading performance in its page experience signals, so it is worth the effort.

Alt text, file names and hidden data

• Alt text. Describe the image in a short, natural sentence, such as “Comparison of a PNG, a JPG and a WebP file size”. Alt text helps people who use screen readers and gives search engines context. Do not stuff it with keywords.
• File names. Use clear, lowercase names with hyphens, such as red-running-shoes.webp, and not IMG_4821.webp. Our guide to SEO-friendly slugs uses the same rules.
• Metadata. Photos from phones and cameras can contain hidden information, such as the date, the camera model, and sometimes the GPS location. Before you publish photos, especially pictures taken at home, check whether your tool removes this data.

Images for link previews

When someone shares your page on Facebook, WhatsApp or X, the platform shows a preview image. JPG and PNG are the safest formats for this, at about 1200 × 630 pixels. Other formats may work on some platforms and fail on others. You can read more in our guide to Open Graph and Twitter Cards.

Common mistakes

• Saving photos as PNG. The file can be ten times larger for no visible gain.
• Saving logos and screenshots as heavily compressed JPG. The edges blur and the text gets fuzzy.
• Converting JPG to PNG and expecting better quality. The detail that JPG already removed does not come back. You only stop further loss. You can read about this in our JPG to PNG Converter page.
• Editing and re-saving a JPG again and again. Each save loses a little detail. Work on the original, and export a JPG only at the end.
• Enlarging a small image. The tool has to invent pixels, so the result looks soft. Start with the biggest original you have.
• Uploading huge photos and letting the browser shrink them. Resize before you upload.
• Forgetting the fallback. WebP only on pages where a JPG may be needed.
• No alt text and meaningless file names.
• Using a transparent PNG where a small JPG would do. Transparency is useful only when you need it.

A simple workflow you can follow

1. Keep the original in a safe folder. Never overwrite it.
2. Resize the image to the size you need, using the Image Resizer.
3. Choose the format. Photos: JPG or WebP. Logos and screenshots: PNG or WebP. Pages with transparency: PNG or WebP.
4. Convert with the Image Converter, using a quality of about 80 for lossy formats.
5. Check the result at full size, looking at edges and text.
6. Name the file clearly, add alt text, and set width and height on the page.
7. Test the page and see whether it loads quickly on a phone.

A quick checklist

• Is this a photo (JPG or WebP) or a graphic (PNG or WebP)?
• Do I need transparency?
• Is the image as wide as it needs to be, and no wider?
• Is the file size reasonable, in the range of hundreds of kilobytes or less for a normal web image?
• Did I compare the compressed image with the original?
• Do I have a JPG or PNG fallback where it is needed?
• Does the image have alt text and a clear file name?
• Did I remove private metadata from personal photos?

Common questions

Is WebP better than JPG?
For websites, it usually gives smaller files at similar quality. JPG is still more widely accepted by software and forms.

Does image format affect SEO?
Not directly. It affects page speed and user experience, which matter for visitors and are part of how search engines judge pages.

Why is my PNG so big?
PNG is lossless, and photos contain a lot of detail that cannot be compressed much without loss. Use JPG or WebP for photos.

Can I convert JPG to PNG to improve quality?
No. The detail JPG removed is gone. Converting only prevents further loss from later edits.

Will the transparent background survive a conversion to JPG?
No. JPG has no transparency, so the area is filled with a colour.

What size should a website image be?
About the width of the space where it appears, or up to twice that for sharp results on high-density screens.

Should I delete the original after converting?
No. Keep it, because you cannot recover lost detail from a compressed copy.

Final thoughts

You do not need to memorize every detail. Remember three things: use JPG or WebP for photos, use PNG or WebP when you need transparency or razor-sharp text, and always resize before you convert.

Pick one image on your own site today. Resize it, save it in two formats, and compare the file sizes and the quality. You will see the difference for yourself, and every page you build after that will load a little faster.