Compress PNG images

Make PNG files much smaller and keep them PNG, transparency included. The tool reduces each image to the best palette of up to 256 colors (the trick TinyPNG and pngquant use), then saves an indexed PNG. Batch mode, a target size in KB if you need one. Free, no watermark, and your files never leave your browser.

Images (you can pick several)

No images yet. You can also drop files on this box.

Settings

Compress by
Quality
Output format

Max width (px, optional)
Max height (px, optional)

Changes apply to every image instantly. Aspect ratio is always kept.

How much smaller does a PNG get?

A normal PNG stores every pixel as full 24-bit or 32-bit color and only compresses it losslessly, so screenshots and graphics are often 5 to 20 times bigger than they need to be. Picking a palette of up to 256 colors, and spreading the small rounding errors so gradients don't band, keeps the image looking the same at a fraction of the size. Measured in Chromium with this page at its default Balanced setting (up to 128 colors, 24 Oct 2026):

Original PNG	Compressed PNG
Wikipedia article screenshot 1280×800, 263 KB	89 KB (−66%)
GitHub home page screenshot 1280×800, 194 KB	72 KB (−63%)
Transparent photo (Wikimedia dice) 800×600, 219 KB	50 KB (−77%)
Python logo, transparent 601×203, 82 KB	5 KB (−94%)

The mean pixel difference against the original was between 0.1 and 2.2 on a 0-255 scale, which you can't see at normal size; pick High (256 colors) for images with soft shadows or gradients. Flat UI colors (backgrounds, buttons) are kept exact, so a white page stays pure white. An image that already has 256 colors or fewer is saved losslessly. For photos with smooth gradients, or if you need the smallest file, WebP is usually smaller again; switch the output format to compare.

How it works

Each image is decoded and redrawn on a canvas in your browser, scaled down if it is wider or taller than your limits, and re-encoded. In target size mode the tool tries qualities with a binary search and keeps the highest one that fits under your limit; if even low quality is too big, it also shrinks the dimensions step by step. If the result would be bigger than your original and nothing was resized, the original file is kept. JPG has no transparency, so transparent areas become white; pick WebP or PNG to keep them. Phone photos are rotated the right way up, and EXIF data (including GPS location) is removed.

Which format should I use?

Format	Best for
WebP	Websites. Usually 25 to 35% smaller than JPG at the same quality, keeps transparency, and every current browser shows it. Some upload forms and older apps still only take JPG or PNG.
JPG	Photos for email, forms and upload portals that ask for "under 100 KB" or "under 1 MB". No transparency.
PNG	Screenshots, logos and pixel-exact graphics. Lossless PNG only gets smaller by resizing. "PNG, smaller" cuts screenshots and logos by 60 to 90% and keeps transparency (compress PNG).

Compress website screenshots at the source

If you are compressing screenshots of web pages, skip the extra step. The Shotmint API renders any URL in Chromium and returns a WebP or JPG at the quality you choose, sized to the viewport you ask for:

curl "https://shotmint.creasework.com/v1/screenshot?url=https://example.com&format=webp&quality=70&width=1280" -H "X-API-Key: YOUR_KEY" -o page.webp

A 1280×800 WebP at quality 70 is typically a fraction of the size of the same PNG. Each screenshot is 1 credit. €5 buys 2,000 with no subscription, and credits never expire.

Get 25 free renders a month Try a website screenshot

FAQ

Are my images uploaded? No. Compression runs in JavaScript on this page. Nothing is sent to a server, so it is fine for ID scans and private photos.

How do I compress an image to 100 KB (or 50 KB, 200 KB, 1 MB)? Choose "Target size (KB)", type the number (1 MB = 1024 KB) and pick JPG if the form requires it. Each image is brought under that size.

How do I resize an image without losing quality? Set a max width, pick PNG to keep it lossless, or WebP/JPG at High quality. Shrinking always discards pixels, but downscaled photos look sharp at their new size.

Is there a limit? No file count limit or watermark. Very large photos (over about 50 megapixels) depend on your device's memory. HEIC photos from iPhones need converting to JPG first, since most browsers can't read them.