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

Using the wrong image format can double your file sizes, slow down your website, and waste your storage. JPG, PNG, WebP, HEIC, and AVIF each have specific strengths and weaknesses. Choosing the right one for each image is the simplest way to optimize your media. This guide covers every common format, how each one compresses, and exactly when to use each.

By the end, you'll never guess at image format again — you'll know exactly which one to use for photos, logos, screenshots, and everything in between.

JPG (JPEG): the photo standard

JPG is the most widely used image format in the world. It uses lossy compression, which means it discards some image data to reduce file size. It's designed for photographs and complex images with many colors and gradients.

Strengths:

• Excellent for photographs — handles millions of colors and smooth gradients.
• Small file sizes — typically 5–10× smaller than equivalent PNGs for photos.
• Universally supported — every browser, device, and application can read JPG.
• Adjustable quality — you can trade file size for quality at any level.

Weaknesses:

• No transparency — JPG doesn't support alpha channels.
• Lossy compression — each save degrades quality slightly (generation loss).
• Poor for text and sharp edges — compression artifacts appear around letters and lines.
• No animation — JPG is a static image format.

Use JPG for: photographs, screenshots with many colors, and any image where transparency isn't needed. Use quality settings of 75–85 for web images.

PNG: the quality standard

PNG uses lossless compression, meaning no data is lost. The image looks identical before and after compression. PNG also supports transparency, making it the standard for logos, icons, and UI elements.

Strengths:

• Lossless compression — perfect quality every time.
• Transparency support — alpha channel for logos and overlays.
• Sharp edges — no artifacts around text and lines.
• Wide support — every browser and device reads PNG.

Weaknesses:

• Large file sizes for photos — PNGs of photos are typically 5–10× larger than equivalent JPGs.
• No EXIF support — PNG doesn't store camera metadata.
• No CMYK support — PNG is RGB only, not suitable for print.

Use PNG for: logos, icons, UI elements, diagrams, screenshots with text, and any image with transparency. Don't use PNG for photographs.

WebP: the modern web standard

WebP was developed by Google as a modern replacement for both JPG and PNG. It supports both lossy and lossless compression, as well as transparency and animation. WebP files are typically 25–35% smaller than equivalent JPGs and PNGs.

Strengths:

• Smaller than both JPG and PNG at equivalent quality.
• Supports transparency — unlike JPG.
• Supports animation — a lightweight alternative to GIF.
• Now supported by all major browsers.

Weaknesses:

• Not universally supported in older software — some image editors and CMS platforms don't handle WebP.
• No universal support in email — some email clients can't display WebP.
• Conversion overhead — you need to convert existing images to WebP.

Use WebP for: everything on the web. If your platform supports it, use WebP exclusively. The size savings are significant.

HEIC: the Apple format

HEIC (High Efficiency Image Container) is Apple's default photo format since iOS 11. It uses modern compression that produces files about half the size of equivalent JPGs. If you have an iPhone, your photos are probably HEIC.

The challenge is compatibility. While Apple devices handle HEIC natively, most web platforms, Windows PCs, and Android devices don't. If you need to share iPhone photos online or use them on non-Apple devices, convert them to JPG first.

AVIF: the future format

AVIF is the newest image format, offering even better compression than WebP — typically 50% smaller than JPG at equivalent quality. Browser support is growing but not yet universal. AVIF is best used as a progressive enhancement: serve AVIF to browsers that support it, and fall back to WebP or JPG for others.

Quick reference: which format to use

Converting between formats

Converting between formats is straightforward, but be aware of quality implications. Converting from JPG to PNG doesn't improve quality — the data lost during JPG compression is gone forever. Converting from PNG to JPG applies lossy compression, reducing quality. Always work from the highest-quality original when converting.

For web optimization, the ideal workflow is: start with a high-quality PNG or raw image, resize to the display dimensions, then convert to WebP for the web. This gives you the smallest file with the best quality.

The bottom line

Choosing the right image format is the simplest way to optimize your images. Use WebP for everything on the web when possible. Fall back to JPG for photos and PNG for graphics with transparency. Convert HEIC from iPhones before sharing. The right format can cut your image sizes in half with no visible quality loss — and your pages will load twice as fast.