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

The short answer

• Photos for forms, email and printing: JPG. Every website, app and printer accepts it.
• Screenshots, logos, text and anything with a transparent background: PNG.
• Images on your own website: WebP (or AVIF), which are much smaller at the same quality.
• iPhone photos (HEIC): convert to JPG before uploading them anywhere outside Apple's apps.
• Logos and icons that must stay sharp at any size: SVG.

JPG (JPEG)

JPG is the format of almost every photo. It throws away detail the eye barely notices, so a 12-megapixel photo fits in 2–5 MB instead of 30. You choose how much: at high quality the loss is invisible; at low quality you start to see blocks and smudged edges.

Its weak points are sharp edges and flat colours. Text, screenshots and logos saved as JPG get a faint fuzz around the letters, and JPG has no transparency. Each time a JPG is edited and saved again it loses a little more, so keep the original if you plan to edit again.

PNG

PNG is lossless: every pixel is kept exactly. That makes it the right choice for screenshots, diagrams, signatures on a white or transparent background, and logos. PNG also supports transparency, so a logo can sit on any colour.

For photos, PNG files are large, often five to ten times a good JPG, so convert photos to JPG before uploading them to a form with a KB limit.

WebP and AVIF

WebP (from Google) and AVIF (newer, from the Alliance for Open Media) do both jobs: lossy for photos and lossless for graphics, with transparency. A WebP photo is typically 25–35% smaller than a JPG of the same quality, and AVIF is smaller still.

Every current browser shows both, so they're ideal for websites. Older software, some government portals and many print shops don't accept them, which is why images saved from websites sometimes need converting to JPG or PNG.

HEIC (iPhone photos)

iPhones save photos as HEIC, which is about half the size of a JPG at the same quality. Apple's apps open it, but many Windows programs, Android apps and upload forms don't. Converting to JPG makes the photo work everywhere, with no visible loss.

GIF, SVG, ICO and TIFF

• GIF: short animations. It's limited to 256 colours, so still photos look grainy; use JPG or PNG for those.
• SVG: drawn from shapes instead of pixels, so it stays sharp at any size. Ideal for logos and icons, but not for photos.
• ICO: the icon format for Windows and website favicons, holding several sizes in one file.
• TIFF: a large, lossless format used in printing and scanning. Rarely needed for everyday use.

What a form or website really checks

Upload forms usually check three things: the format (most accept only JPG or JPEG, sometimes PNG or PDF), the file size in KB, and sometimes the width and height in pixels. Changing the file extension by renaming it doesn't convert it; the file inside stays the same and is often rejected. Convert it properly, then compress it to the size the form asks for.

Frequently asked questions

Which is better, JPG or PNG?

For photos, JPG: the file is far smaller and the difference isn't visible. For screenshots, text, logos and anything with transparency, PNG, because it keeps edges sharp and supports a transparent background.

Is WebP better than JPG?

For websites, yes: WebP is about a quarter to a third smaller at the same quality. For forms, printing and older software, JPG is safer because almost everything accepts it.

Does converting PNG to JPG lose quality?

A little, because JPG compresses the image, but at high quality the change isn't visible in photos. Transparent areas become a solid colour (usually white), since JPG has no transparency.

Can I just rename a file from .png to .jpg?

No. Renaming changes only the name, not the data inside, so many programs and upload forms reject it. Use a converter to change the format properly.