JPG, PNG, WebP or HEIC: which image format to use when

Most people never choose an image format; the phone or the screenshot tool chooses for them. That works until a form refuses the file, an email bounces because it is too large, or a logo gets an ugly white box around it. Four formats cover almost everything, and each is good at something different.

JPG: the format for photos

JPG (also written JPEG) has been the standard for photos since the 1990s, and every device, program and upload form accepts it. It compresses with loss: it throws away detail the eye barely notices, which makes photos small. The price is that sharp edges, text and flat colours get blurry or blocky, and that every new save loses a little more.

Use it for photos, online forms and anything that has to work everywhere.

PNG: the format for graphics and screenshots

PNG is lossless: what you save is exactly what you get back. It also supports transparency. That makes it right for screenshots, text, logos, charts and icons, and wrong for photos, which become several times larger than as a JPG.

Use it for screenshots, logos, anything with text or a transparent background.

WebP: smaller files for the web

WebP was developed by Google for websites. At similar quality, a WebP photo is typically 25–35 percent smaller than a JPG, and WebP can also be lossless and transparent like PNG. Every current browser shows it. The catch: some older programs and many upload forms still do not accept it.

Use it for images on your own website. For forms and email attachments, convert to JPG with WebP to JPG.

HEIC: the iPhone format

Since iOS 11 (2017), iPhones save photos as HEIC by default. It needs about half the space of a JPG at similar quality, which is why Apple uses it. Outside Apple devices it is still awkward: many Windows programs, websites and forms cannot open it.

Use it for storing photos on an iPhone. To share or upload them, convert with HEIC to JPG.

Which format for which job

Converting without surprises

• PNG to JPG makes photos much smaller (PNG to JPG). Transparent areas become a solid colour, so pick white or another background.
• JPG to PNG does not bring lost detail back (JPG to PNG). Use it only when a program insists on PNG.
• JPG to WebP saves space on websites (JPG to WebP).
• Convert once, from the original. Each lossy conversion costs a little quality; going back and forth adds up.

All conversions in ShrinkLab run in your browser, so your photos are never uploaded. The image converter handles all four formats and many more.