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

Every image you save is a quiet decision about quality, file size, and compatibility. Choose JPG for a logo and the edges turn fuzzy. Choose PNG for a photo and the file balloons to ten times what it should be. The three formats are not interchangeable — each was designed for a different kind of picture.

Here is the practical version, without the engineering lecture.

JPG (JPEG): for photographs

JPG uses lossy compression tuned for the smooth gradients and fine detail of real-world photos. It throws away information your eye barely registers, which is why a photo saved as JPG can be a fraction of the size of the same image as PNG, with no obvious difference.

• Best for: photographs, screenshots of photos, anything with lots of colours and gradients.
• Weakness: no transparency, and it adds visible "noise" around sharp edges and text.
• Watch out: every time you re-save a JPG it loses a little more quality. Keep an original.

PNG: for graphics, logos, and transparency

PNG is lossless — it reproduces every pixel exactly. That makes it perfect for images with hard edges, flat colour, and text: logos, icons, diagrams, and screenshots of interfaces. Crucially, PNG also supports transparency, so a logo can sit on any background without an ugly white box around it.

• Best for: logos, icons, line art, charts, screenshots of apps, anything needing a transparent background.
• Weakness: photos saved as PNG are enormous because lossless compression cannot do much with photographic detail.

WebP: the modern all-rounder

WebP is a newer format from Google that can do both jobs. It offers lossy compression that beats JPG on size (typically 25–35% smaller at the same quality) and a lossless mode with transparency like PNG. For the web, it is often the best of both worlds.

The catch used to be support, but that is mostly history now — every current browser handles WebP. The main place you still hit friction is older software, some email clients, and the odd upload form that only accepts JPG or PNG.

• Best for: images on your own website where you control the page and want fast loading.
• Weakness: not universally accepted by third-party tools and upload forms yet.

A 10-second decision guide

1. 1Is it a photo? → JPG (or WebP if it is for your own website).
2. 2Does it need a transparent background, or is it a logo / icon / screenshot of an app? → PNG (or WebP).
3. 3Is it going on a website you control and you want it as small as possible? → WebP.
4. 4Are you uploading to a form or sending to someone and not sure what they support? → JPG or PNG, the safe defaults.

A note on size vs format

Format is only half the story. A 4000-pixel-wide photo is heavy no matter what you save it as. If an image only needs to display at 800 pixels wide on a page, resize it down first — that single step usually cuts the file size more than any format change. Resize, then choose the right format, then compress: in that order you will get the smallest possible file that still looks great.