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July 1, 2026 · 6 min read
PNG is a lossless format, which is exactly why its files get so big: it stores every pixel perfectly instead of throwing detail away. That's great for crisp logos and screenshots, but a single PNG can easily run to several megabytes — far too heavy for a web page or an email. The good news is that you can usually cut a PNG's size by 50–90% without any visible loss. Here are the four methods that actually work, from gentlest to most aggressive.
A PNG records the exact colour of every pixel, and a full-colour PNG (called PNG-24) can store over 16 million colours. For a photograph that's a huge amount of data — which is why a photo saved as PNG is typically five to ten times heavier than the same photo as JPEG. PNG only compresses well when an image has large areas of flat, repeated colour, like a logo or a diagram.
So the first question is always: what's actually in the image? The answer decides which method below will help most.
If your image is a logo, icon, illustration or screenshot with a limited palette, you rarely need 16 million colours. Converting from PNG-24 to PNG-8 reduces the image to a palette of up to 256 colours, which can shrink the file by 60–80% with no visible difference on flat-colour graphics.
This is the single biggest win for graphics. It only hurts on images with smooth gradients or photographic detail, where 256 colours aren't enough and you'd see banding — in that case, use method 3 or 4 instead.
File size grows with the number of pixels, so a 4000-pixel-wide PNG holds roughly four times the data of a 2000-pixel one. If the image is displayed much smaller than its actual resolution — which is almost always the case — resizing it to the size it's really shown at is free, instant savings.
Decide how wide the image actually appears (a little extra for high-resolution screens is fine), then resize to that width before doing anything else. On its own, resizing can cut file size by 75% or more.
Most PNGs exported from design tools, phones or screenshots contain redundant data and aren't optimally compressed. A good PNG compressor re-encodes the image and strips unnecessary metadata, typically saving 20–50% with zero quality loss — the pixels stay identical, the file just gets packed more efficiently.
Our compressor does exactly this in your browser: drop the PNG in, and it re-compresses it locally without uploading anything. Combine it with a colour reduction for the biggest effect.
The biggest reductions come from leaving PNG behind when it isn't the right tool. If your image is a photograph and doesn't need a transparent background, save it as JPEG or WebP instead — you'll often go from 4 MB to under 300 KB with no visible difference. If you do need transparency but want it lighter, lossless WebP keeps the transparent background while beating PNG on size.
A simple rule: keep PNG for flat-colour graphics and anything transparent; switch to JPEG or WebP for photos. Whatever you choose, drop the file into our compressor to squeeze out the last kilobytes — everything runs locally, so your image never leaves your device.