Free PNG Compressor: Reduce PNG File Size Online
This PNG compressor shrinks images in your browser while keeping transparency. Reduce colors, resize, or set a target size like 100 KB, 1 MB or 2 MB, compare before and after, and download a single file or a ZIP. Free, no sign-up, and your files never leave your device.
By Troopus · Updated: October 24, 2026
- 🪟 Keeps transparency
- 🎯 Target size: 100 KB, 1 MB, 2 MB
- 📦 Batch + ZIP
- 🔒 Nothing uploaded
PNG compressor online free: compress your images
Nothing is uploaded: compression runs in your browser. PNG is a lossless format, so file size only drops by reducing colors or dimensions. The ZIP contains every compressed image.
How do I compress PNG without losing quality?
To compress a PNG without losing quality, drop the file into the tool above and keep the color reduction set to "Do not reduce". The PNG is re-saved losslessly, so every pixel stays identical. For a bigger drop in file size, reduce the dimensions or the number of colors and check the before and after preview.
This PNG compressor reads your image, redraws it, and saves it again with the settings you choose. Here is the quickest way to use it:
- Add one or more images by dragging them in, tapping the drop area, or pasting with Ctrl+V.
- Pick By quality to compress with fixed settings, or Target file size to fit a limit such as 100 KB.
- Optionally set a maximum width or a color reduction level.
- Compare the before and after images, then download one file or a ZIP of all of them.
Be realistic about lossless mode. A browser can only re-encode a PNG, not rebuild it with a smarter encoder, so a PNG that was already exported well may not shrink at all. When that happens the tool says so, and keeping the original is the right call. Real savings come from fewer colors, fewer pixels, or a different format.
Lossy vs lossless: how does a PNG compressor shrink files?
PNG itself is always lossless, so "lossy PNG compression" really means reducing the number of colors before saving. Lossless compression keeps every pixel exactly. Lossy PNG tools merge similar shades into fewer colors, which can cut file size sharply but may add visible banding in gradients and photos.
The PNG format stores pixels with a lossless compression method, so the "loss" in lossy PNG tools always happens before saving. Tools like pngquant do this by building a limited color palette. This page does a simpler version of the same idea: it rounds each color channel to a fixed number of levels, then saves a normal PNG.
| Setting | Levels per channel | Best for |
|---|---|---|
| Do not reduce | 256 (original) | Exact pixels, screenshots with text |
| Light | 64 | Most graphics and UI images |
| Medium | 32 | Logos, flat illustrations |
| Strong | 16 | Icons and simple art |
| Maximum | 8 | Posterized, very simple images |
This is not a true indexed PNG-8 palette, so results will differ from dedicated desktop tools, and gradients can show visible steps. Use the preview to decide, and zoom in on smooth areas such as skies, skin and shadows first.
How to compress PNG to 100KB or compress PNG to 2MB
To compress a PNG to 100 KB, 1 MB or 2 MB, open "Target file size", click a preset or type your limit, and let the tool search for a result that fits. It reduces colors step by step first, then shrinks the dimensions if you allow it, and it tells you honestly when a limit is out of reach.
Upload forms often cap images at 100 KB, 1 MB or 2 MB. Because PNG has no quality slider, the tool tries these steps in order for each image and stops at the first one that fits:
- The image at full size with its current colors.
- Color reduction at 64, 32, 16 and then 8 levels per channel (if "allow reducing PNG colors" is ticked).
- Smaller dimensions, tested in steps (if "allow shrinking dimensions" is ticked).
If nothing reaches the limit, you get the closest result plus a clear message. A very large screenshot may simply need a lower maximum width, or a switch to WebP or JPG. The exact size appears in the list after every run.
| Limit | Bytes |
|---|---|
| 100 KB | 102,400 |
| 1 MB | 1,048,576 |
| 2 MB | 2,097,152 |
The tool counts 1 KB as 1,024 bytes. If a website counts 1 KB as 1,000 bytes and is strict, aim a little under its limit.
Does compressing a PNG keep transparency?
Yes, compressing a PNG here keeps transparency as long as the output format stays PNG or WebP. The alpha channel is preserved, and color reduction only touches the red, green and blue values. Saving as JPG removes transparency, because JPG has none, and fills those areas with the background color you choose.
Logos, icons, stickers and cutouts depend on transparent areas, so the tool treats them carefully. The PNG and WebP outputs keep the alpha channel. If you convert to JPG, transparent pixels are filled with the color picker value, white by default.
One honest caveat: browsers store canvas pixels with premultiplied alpha, so color values in semi-transparent edge pixels can shift very slightly after re-saving. This is rarely visible, but for production artwork with soft shadows, check the result on a dark and a light background before replacing the original.
PNG vs JPG vs WebP for smaller files
Use PNG for logos, screenshots and graphics that need sharp edges or transparency, JPG for photos, and WebP when you want the smallest file with either. Photos saved as PNG are often several times larger than the same photo as JPG or WebP, so converting is usually the biggest saving.
Choosing the right format often beats any compression setting. This tool can convert as it compresses, so you can test each one on your own image:
| Format | Compression | Transparency | Best for |
|---|---|---|---|
| PNG | Lossless | Yes | Logos, screenshots, line art |
| JPG | Lossy | No | Photos |
| WebP | Lossy or lossless | Yes | Web images of any kind |
For photos, a JPG or WebP quality between 70 and 85 % is usually a good start. WebP is supported by all current major browsers, but older apps and some upload forms still reject it, so check what your destination accepts. If you only need different dimensions, a quick maximum width such as 1920 px already removes a lot of weight.
If you are building a QR code to print or share, our QR code generator exports a clean PNG you can compress here.
Does the PNG compressor upload my images?
No, your images are not uploaded anywhere. This PNG compressor runs entirely in your browser using the canvas feature, so files never leave your device. There is no account, no server storage and no network request for your images. That also makes it safe for screenshots, IDs and client work.
Everything happens on your device: the file is read locally, redrawn on a canvas, encoded in memory and offered as a download. You can confirm it by opening your browser developer tools, watching the network tab while you compress, and seeing that no image data is sent. Large images need memory, so very big files (tens of megapixels) may fail on older phones, and the tool will tell you if that happens.
Limits: up to 40 images per batch, and the ZIP is built in your browser too. Remember that images can carry metadata such as camera data or location. Re-saving through a canvas drops that metadata, which is a privacy benefit but also means the original file details are gone from the output.
Frequently asked questions
How can I reduce PNG file size without losing quality?
Lossless saving keeps every pixel but rarely shrinks an already optimized PNG much. To cut size meaningfully, reduce the dimensions, try a light color reduction, or convert photos to WebP or JPG. Always compare the before and after preview to confirm you accept the result.
Why are PNG files so large?
PNG stores every pixel without discarding detail, and photos or gradients contain many unique colors that compress poorly. A photo saved as PNG is often several times larger than the same photo as JPG. Screenshots and flat graphics compress much better.
Does PNG compression keep transparency?
Yes. Compressing to PNG or WebP keeps the alpha channel, and color reduction does not change transparency values. If you choose JPG, transparent areas are filled with your chosen background color because JPG cannot store transparency.
How do I compress a PNG to under 100KB?
Open Target file size, click the 100 KB preset and add your image. The tool tries color reduction first, then smaller dimensions if allowed. Large images may need a lower maximum width. If the limit is out of reach, it shows the closest result and says so.
Is it safe to compress PNG online?
It is safe with this tool because nothing is uploaded: compression runs in your browser and files stay on your device. With any other online compressor, check whether it uploads your images to a server, especially for private documents or client work.
Is a PNG optimizer the same as a PNG compressor?
Mostly yes. A PNG optimizer re-saves the file with better lossless settings, and a PNG compressor like this one can also reduce colors or dimensions. Lossless saving keeps every pixel, while the extra steps trade some detail for size, so check the preview.
Can I compress multiple PNGs at once?
Yes, up to 40 images per batch. The same settings apply to all of them, the list shows the size before and after for each file, and you can download everything as one ZIP or one file at a time.
Why did my PNG get bigger after compressing?
Some PNGs are already tightly optimized, and re-encoding in a browser can produce a slightly larger file. The tool flags this. Keep the original, or reduce dimensions or colors, or switch to WebP if the destination accepts it.