Upload the same photo as a JPEG, a PNG, and a WebP, and you’ll get three different file sizes and three different sets of trade-offs — yet most people pick a format out of habit, not because it’s actually the right one for the image. Here’s what each format is actually good at, and a free image compressor below to shrink whichever one you end up using.
The three formats, in plain terms
- JPEG (.jpg): “Lossy” compression built for photos. It throws away image data you’re unlikely to notice to get small file sizes. Great for photographs, bad for text, logos, or flat-color graphics (it introduces visible blur/fuzz around sharp edges).
- PNG (.png): “Lossless” compression — every pixel is preserved exactly. Supports transparency. Great for screenshots, logos, icons, and anything with sharp edges or text. Bad for photos (file sizes get large fast compared to JPEG).
- WebP (.webp): A newer format from Google that does both lossy and lossless compression, usually beating JPEG and PNG at their own jobs by 25–35% smaller file size at the same visual quality. Supports transparency like PNG. The only real downside: a small number of older tools and some email clients still don’t handle it well.
Which one should you actually use?
- Photos for a website: WebP first choice, JPEG as a fallback if you need maximum compatibility.
- Logos, icons, screenshots, or anything with transparency: PNG, or WebP if your platform supports it — both preserve sharp edges and transparent backgrounds that JPEG would blur or fill with a solid color.
- Email attachments or documents going to older software: JPEG or PNG — WebP support is inconsistent outside the browser.
- Social media uploads: most platforms re-compress whatever you upload anyway, so JPEG is the safest universal choice there.
File size: what the difference actually looks like
A 2000×1500 photo that’s roughly 3.2 MB as an uncompressed PNG typically comes down to 400–600 KB as a JPEG at good quality, and 280–400 KB as a WebP at the same visual quality — which matters directly for page load speed, since large images are usually the single biggest thing slowing a web page down. A screenshot or logo behaves the opposite way: a PNG screenshot with large flat color areas can be smaller than the same image saved as JPEG, because JPEG’s compression is tuned for photographic noise, not flat color.
Quality settings: the trade-off that matters most
For lossy formats (JPEG and lossy WebP), quality is usually a 0–100 slider. Dropping from 100 to around 80 typically cuts file size by half or more with almost no visible difference to the human eye — most of the “savings” in that range are genuinely invisible. Below about 60, compression artifacts (blockiness, blur around edges, color banding) start becoming visible, especially in images with fine detail or text. There’s no universal “correct” number; the right move is comparing the compressed result side-by-side with the original at the size it’ll actually be displayed.
A quick way to check
Run the same image through a compressor at a few different quality levels and compare the resulting file sizes and the visible quality yourself — what looks fine at 70% quality for one photo might show visible artifacts on another, depending on how much fine detail or flat color it has. ToolNixy’s compressor runs entirely in your browser, shows the before/after size difference directly, and automatically disables the quality slider for PNG uploads since lossless compression doesn’t have a quality dial to begin with.
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