JPG (Joint Photographic Experts Group) was created in 1992 and remains the most universally supported image format. It uses lossy compression — meaning it permanently discards some image data when saving, resulting in smaller files at the cost of minor quality loss.

The compression works by breaking the image into 8×8 pixel blocks and averaging similar colors within each block. For photographs with smooth gradients and natural color transitions, this is nearly invisible. For sharp geometric edges, text, or flat colors, it creates visible “compression artifacts” — blocky distortions around edges.

File size: A 12 MP smartphone photo is typically 2–5 MB as JPG at standard quality.
Quality settings: JPG quality ranges from 1–100%. 85–95% is the sweet spot for most uses.

Use JPG for:

• Photographs and photographic images
• Social media posts and profile pictures
• Email attachments with photographic content
• Web images where file size matters and sharpness is not critical
• Printing photographs

Don’t use JPG for: Logos, icons, text-heavy graphics, screenshots, anything with a transparent background, or images you’ll edit multiple times (re-saving degrades quality each time).

PNG (Portable Network Graphics) was created in 1996 as a patent-free replacement for GIF. It uses lossless compression — every pixel is preserved exactly. No data is discarded, so quality never degrades regardless of how many times you save the file.

PNG’s killer feature is its alpha channel — it stores transparency per pixel. This makes PNG the standard for logos, icons, and interface elements that need to sit on colored or varying backgrounds without a white box around them.

The tradeoff is file size. For photographic content, PNG files can be 3–5× larger than equivalent JPGs, because lossless compression of complex photographic data is inefficient. PNG shines for images with large areas of flat color, sharp edges, or text.

Use PNG for:

• Logos and brand graphics that need sharp edges
• Icons and interface elements
• Screenshots (preserves text sharpness)
• Images with transparent backgrounds
• Intermediate files during editing (no quality degradation)
• Infographics with text and flat colors

Don’t use PNG for: Large photographic images on websites (use JPG or WebP instead — PNG photos are unnecessarily large), or anything where file size is critical.

WebP was developed by Google and released in 2010. It uses modern compression algorithms (derived from the VP8 video codec) to achieve 25–35% smaller file sizes than JPG at the same visual quality. It also supports transparency like PNG, and even animation like GIF.

Browser support is now universal — Chrome, Firefox, Safari, Edge, and Opera all support WebP. iOS has supported it since Safari 14 (2020) and Android since Chrome for Android. The only remaining gap is older software — some desktop photo editors, older Windows applications, and some CMS platforms still don’t handle WebP natively.

Use WebP for:

• All images on modern websites — the single best choice for web performance
• Any image served on a platform where you control the delivery format
• Logos and icons that need transparency but also small file sizes

Don’t use WebP for: Email attachments (many email clients don’t support it), files shared with users who may use older software, print production, or anywhere you’re unsure about software compatibility.