Compress PNG
Make a PNG smaller without losing its transparent background. It happens in this browser tab, so the files never leave your device, and there is no limit on how many you do.
nothing was uploaded
Why a PNG is so big, and what actually makes it smaller
A PNG stores every pixel exactly as it was given: three bytes of colour and, if it has transparency, a fourth byte of alpha. That is why it is the right format for a cutout and the wrong one for a photograph. A 12-megapixel photo saved as PNG is tens of megabytes, and the same picture as JPG is two.
The PNG format also has a second, quieter mode: instead of a colour per pixel it can store a table of up to 256 colours and then one number per pixel saying which of them to use. For a photograph that sounds ruinous, and for a cutout it usually is not: put the two side by side and the difference is hard to find, while the file is between a half and a fifth of the size. That is what this page does, and it is what every PNG compressor worth using does.
Transparency survives it
The thing most palette compressors get wrong is the alpha. A cutout's edge is not opaque or transparent, it is a ramp through every value in between, which is what makes hair look like hair. A compressor that treats transparency as an afterthought spends its whole table on the opaque middle of the subject and leaves that ramp in three or four steps, which shows as a hard, stepped outline.
Here transparency is part of the colour from the start, so the table is spent where the picture needs it. A cutout keeps its soft edge, and a picture with no transparency at all is not given any.
What it will not do
It will not make a file bigger. Artwork with few colours, and a PNG somebody has already compressed, can come back larger after a round trip; when that happens the original is handed back untouched and the row says so, rather than quietly growing your file.
It will not resize your picture either. The dimensions that went in are the dimensions that come out, because a compressor that silently shrinks a photo is solving a different problem from the one you asked about. If a smaller picture is what you want, the PNG to WebP converter will usually beat any PNG for a website, and the background remover has canvas sizes for social media.
Guides that go further
Part of the formats behind your photos. What each format is, when to use it, and what to do when a file will not open.
- How to reduce a PNG's file size without losing transparencyReduce PNG file size by resizing, cutting colours and lossless optimising, with free PNG optimizer tools that keep transparency and run on your own device.
- PNG vs WebP for websites: which should your images be?WebP vs PNG for a website: file size, transparency, browser and CMS support, and the few places a PNG is still the better choice, with numbers and examples.
- Photo file formats: HEIC, JPG, PNG, WebP, AVIF and more, explainedPhoto file formats compared: which keep transparency, which every app opens, and what to turn a HEIC, AVIF, WebP or JFIF into before you edit or share it.
- What is a transparent background, really?A transparent background is empty pixels, not white ones. How alpha works, why editors show a checkerboard, and which formats keep it: PNG, WebP, AVIF, not JPG.
Questions
How do I compress a PNG for free?
Drop the PNG files on this page, or choose them. Each one is compressed in your browser and appears in the list with its old size, its new size and how much smaller it got, with a Save button, or Save all to get them in one ZIP. There is no account, no limit on the number of files and no watermark.
Does compressing a PNG lose the transparent background?
No. The transparency is kept, including the soft edges of a cutout. The palette this tool builds treats transparency as part of a colour, so a hair edge that fades out stays a fade rather than becoming a hard line.
Is this lossless?
No, and nothing that makes a photographic PNG much smaller is. The saving comes from storing at most 256 colours instead of sixteen million, which for a photo or a cutout is usually impossible to see side by side and is what every PNG compressor does. The shape of the picture, its size in pixels and its transparency are untouched.
How much smaller will my file get?
Most photographic PNGs come back between a half and a fifth of what they were. A screenshot of flat colour is often already small and may barely change. The page shows the before and after for every file, so you can see rather than guess.
Why did one of my files not get smaller?
Because it was already at least as small as this could make it, which happens with artwork that has few colours or a PNG somebody has already compressed. When that happens the original file is handed back untouched rather than a larger one, and the row says so.
What does Smooth gradients do?
It spreads the rounding error from each pixel into its neighbours, which turns the banding you would otherwise see across a sky or a soft shadow into a fine texture. It is worth leaving on for photographs and worth turning off for flat artwork, where it only adds noise and a little size.
Are my pictures uploaded?
No. The compression happens inside this browser tab and getPNG has no server that could receive a picture. You can check it: open the browser's network tab while you compress a file and no request carries the image.
Can I compress a JPG here?
You can drop one and you will get a PNG back, but that is rarely what you want: a JPG is already compressed for photographs and a PNG of the same picture is usually larger. This page is for PNGs that are bigger than they need to be.
Your files never leave this device
Most online converters upload every file to a server, convert it there and keep it for a while. Here your browser decodes and encodes the picture itself, so there is nowhere for the file to go. You can check it: load this page, switch the browser to offline, and convert a file. How to check a site is not uploading your photos.