Pick the wrong image format and you either lose quality or bloat your file for no reason. It is a decision people make dozens of times a week without thinking, and getting it right quietly improves everything from website speed to how sharp your logo looks. The topic is usually made more complicated than it needs to be — here is the version that actually helps.
We will look at how each of the three main web formats compresses images, what each is genuinely best at, the mistakes people make when choosing, and a simple decision guide you can apply in seconds.
JPG (also written JPEG) uses lossy compression, meaning it discards detail the human eye barely notices in order to keep files small. That trade-off is ideal for photographs and any image with lots of colours and smooth gradients, where the discarded data is genuinely imperceptible.
Its limitations are equally clear. JPG does not support transparency, so it cannot sit cleanly over a coloured background. And because it is lossy, re-saving the same JPG repeatedly slowly degrades it — each save throws away a little more. Edit from an original whenever you can, and export to JPG once at the end.
PNG uses lossless compression, preserving every pixel exactly. This makes it the right choice for images with sharp edges and flat colour: logos, icons, diagrams, screenshots, and anything containing text. It also supports full transparency, which is why designers reach for it when an image needs to overlay other content.
The cost is file size. For a photograph, a PNG can be several times larger than the equivalent JPG with no visible benefit, so it is the wrong tool for photos. If you have a JPG that needs a transparent background or lossless edits, the JPG to PNG converter moves it across in one step.
WebP is the newest of the three and, for web use, usually the best default. It offers both lossy and lossless compression, supports transparency and animation, and produces smaller files than JPG or PNG at equivalent quality. In effect it combines the strengths of both older formats.
Because every current browser supports it, there is little downside to using WebP for website imagery. Convert any JPG or PNG with the WebP Converter, and keep a traditional-format copy only if you need to send the image somewhere outside the web.
Most choices come down to a single question about what the image contains and where it is going:
A few habits cause most of the quality and size problems people run into:
Whichever format you choose, compression is the final step that keeps files lean. Even a well-chosen WebP or JPG usually contains metadata and quality headroom you can safely trim. Running the file through the Image Compressor removes that excess without a visible change.
Think of format and compression as two separate decisions: the format determines how the image is stored, and compression determines how much of that storage is genuinely necessary. Get both right and your images look sharp while loading fast.
JPG, PNG, and WebP cover most needs, but two other formats deserve a mention because they are the right answer in specific situations.
The practical takeaway: use SVG for anything that is drawn rather than photographed and needs to scale, and reach for WebP over GIF whenever you need a short animation. Together with JPG, PNG, and WebP, these cover essentially every image you will ever need to publish on the web.
For lossy formats like JPG and WebP, you choose a quality level when you export, usually on a scale from 0 to 100. Higher means better quality and larger files; lower means smaller files with more visible compression. The mistake most people make is defaulting to maximum quality, which produces needlessly heavy files.
In practice, a quality setting around 75–85 is the sweet spot for web images: the difference from maximum quality is invisible to the eye, while the file is significantly smaller. Below about 60, compression artefacts start to show, especially in areas of smooth colour or fine detail. When compressing, nudge the quality down until you can just start to notice a difference, then step back up one notch — that is your optimal setting for that image.
The web is not the only place your images travel, and social platforms and email have their own quirks worth knowing. Getting the format right for each avoids the frustration of a logo that looks fine on your site but blurry in a post.
The theme across all of these is compatibility over cleverness. On your own website you control the environment and can use WebP freely; when you hand an image to a platform or an inbox you do not control, the safe, widely-supported formats — JPG for photos, PNG for graphics — reduce the risk of it displaying badly. Save WebP's efficiency for the contexts where you know it is supported.