JPG vs PNG vs WebP: Which Image Format to Use and When to Convert
Almost every image you handle online is one of three formats: JPG, PNG or WebP. They look the same in a preview, but they are built for different jobs, and using the wrong one quietly costs you either quality or megabytes. Knowing which is which lets you make files that are smaller, sharper, or compatible exactly when you need each property.
This guide explains what each format is genuinely good at, the traps to avoid, and when converting between them is worth the effort.
JPG: photographs and smooth gradients
JPG (or JPEG) uses lossy compression tuned for photographs. It excels at images with smooth colour transitions — landscapes, portraits, anything camera-shot — and can shrink them dramatically with little visible loss. That is why it remains the default for photos across the web.
Its weaknesses are sharp edges and text. Compress a screenshot or a logo with crisp lines as a JPG and you will see fuzzy "halos" around the edges, called compression artefacts. JPG also cannot store transparency, so it always fills the background with a solid colour.
PNG: sharp edges, text and transparency
PNG uses lossless compression, meaning it preserves every pixel exactly. That makes it the right choice for screenshots, logos, diagrams, line art and anything with hard edges or text — all the cases where JPG struggles. Crucially, PNG also supports transparency, which is why signature stamps, logos and UI assets are almost always PNGs.
The cost is file size. For a photograph, a PNG can be five to ten times larger than an equivalent JPG with no visible benefit, because lossless compression cannot exploit the eye's tolerance for tiny photographic imperfections. Use PNG for graphics, not for holiday photos.
WebP: the modern all-rounder
WebP is a newer format that does both jobs: it offers lossy compression that beats JPG and lossless compression that beats PNG, plus transparency in both modes. For the web, converting images to WebP typically cuts page weight noticeably with no perceptible quality loss, which is why so many sites have adopted it.
The catch is compatibility. While modern browsers handle WebP fine, some older software, email clients and printing workflows still expect JPG or PNG. So WebP is excellent for serving images on a website, but you may need to convert back to JPG or PNG when sending a file to someone whose tools are less current.
When converting is actually worth it
Converting is not about chasing the "best" format in the abstract — it is about matching the format to the destination.
- Shrinking photos for email or upload: convert to JPG, or to WebP if the recipient supports it. Use the Compress Image tool to hit a target size.
- A logo or screenshot that looks fuzzy as a JPG: convert it to PNG to restore the sharp edges.
- Need transparency for a stamp or overlay: PNG or WebP, never JPG.
- A WebP someone else cannot open: convert it back to JPG or PNG with the Convert Image tool.
Frequently asked questions
Does converting JPG to PNG improve quality?
No. Converting to PNG cannot recover detail already lost to JPG compression — it just stores the existing pixels losslessly, usually at a larger size. Convert to PNG only when you need sharp edges or transparency going forward.
Is WebP always smaller than JPG?
Usually, for the same visible quality. The main trade-off is compatibility with older software rather than file size.
How do I make an image fit a size limit?
Use the Compress Image tool to reduce file size, and convert to an efficient format (JPG or WebP) if you started from a large PNG.