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What Image Format Should I Use for My Website?

Not sure which image format to use? This decision framework maps each common image type to the best format, so you can stop guessing and start shipping faster pages.

Start With the Content, Not the Format

The right format follows from what the image actually shows, not from a preference. Photographs want small lossy files; graphics want crisp lossless ones; anything with transparency needs a format that stores an alpha channel. Answer "what is this image?" first, and the format chooses itself.

Decision Table

Match the image to the format.
If your image is…Use
A photographJPG or WebP
A logo or iconPNG or SVG
A screenshot with textPNG or WebP
A hero with transparencyWebP or PNG
An animated graphicWebP or AVIF (not GIF)
The smallest possible fileAVIF (with WebP fallback)

Walking Through Common Cases

Photographs

A portrait, a landscape, a product shot — these are JPG by default, WebP if your stack serves it. Smooth gradients hide compression beautifully, so you get the smallest files with no visible cost.

Logos and Icons

Anything with text or a hard edge must stay sharp, so PNG (or vector SVG for truly simple marks) is correct. JPG here produces fuzzy edges and ringing around letters — an instant signal of an unpolished site.

Screenshots and Diagrams

Screenshots contain text and flat color, so lossless PNG or WebP keeps them legible. A JPG screenshot develops smeared text and colored noise in solid areas.

When in Doubt

If you remember one rule: photos are JPG, everything else is PNG. Then upgrade to WebP or AVIF wherever your visitors’ browsers allow it. That single habit resolves the vast majority of format questions without a second thought.

Format is a means, not an end

The goal is a fast, sharp, correct image. Format is just the lever that gets you there — pick it from the content, not from fashion.

Compare JPG vs PNGThe everyday format question, answered.

Frequently Asked Questions

Is JPG or PNG better for websites?

Use JPG for photos and complex images where file size matters, and PNG for graphics, logos, and anything that needs transparency. JPG keeps pages light; PNG keeps edges crisp.

Does PNG lose quality when saved?

No. PNG uses lossless compression, so it preserves every pixel exactly. JPG is lossy and discards some data each time you save at a lower quality setting.

Which is smaller, JPG or PNG?

For photographs, JPG is almost always much smaller. For simple graphics with flat colors, PNG can be smaller because it compresses solid areas very efficiently.

Can JPG have a transparent background?

No. JPG does not support transparency. If you need a transparent background, convert to PNG or WebP instead.