JPG to PNG

Convert JPG photos to lossless PNG in your browser, with optional palette and grayscale optimisation and no upload.

Drop your files here

.jpg, .jpeg, .jpe, .jfif · up to 100 MB

Choose files

How to Convert to PNG

1
Drop your JPG files
Up to 100 at a time. Files named .jpg that turn out to hold something else are handled by what is actually inside them, not by the extension.
2
Choose an optimisation level
Level 2 is the sensible default. Level 6 spends several times longer looking for a smaller lossless encoding of exactly the same pixels.
3
Download the PNGs
The result is usually larger than the JPG; that is what lossless means. One file downloads directly, several arrive as a ZIP.

What this conversion does and does not do

The JPG is decoded to pixels and those exact pixels are written into a PNG. Nothing is added and nothing further is lost: the PNG is a perfect record of what the JPG contained. What it cannot do is undo the compression that already happened. If the original JPG has visible blocking or soft edges, the PNG will have exactly the same blocking and the same soft edges, stored losslessly. People usually want this conversion for one of three reasons: an editor or a printing service that refuses JPG, a screenshot going into documentation where repeated re-saving would degrade a JPG, or as the first step before making the background transparent, which needs an alpha channel that JPG does not have.

Optimisation levels, colour types and why PNGs get big

PNG size depends on two things: how many bytes each pixel needs, and how well the row-by-row compression works. The colour type setting controls the first. Automatic lets the optimiser pick the smallest type that is still exactly lossless: a grayscale photo drops to one channel, and a chart with under 256 distinct colours becomes a palette image and can shrink several times over. You can also force a type if you have a downstream tool that insists on one. The optimisation level controls the second: higher levels try more filter combinations per row and repack the compressed stream harder. Level 0 is instant, level 2 costs a fraction of a second and gets most of the benefit, level 6 can take several seconds on a large photo for another few percent.

Your file stays on your device

The JPEG decoder, the PNG encoder and the optimiser are all WebAssembly modules running inside your browser tab. Your photo is never uploaded, there is no server-side queue, and everything is gone from memory the moment you close the page. Camera photos with GPS coordinates in them stay entirely under your control.

Frequently asked questions

Will the image quality improve after converting to PNG?

No. PNG is lossless, which means it records what it is given perfectly, including every artefact the JPG compression already introduced. Converting does not recover detail that was thrown away when the JPG was made. It does mean no further quality is lost on subsequent saves, which is the real reason to do it.

Why is the PNG so much bigger than the JPG?

JPG throws away information the eye barely notices and can therefore hit very small sizes. PNG throws nothing away, so it has to store the full detail of every pixel, including the fine noise that JPG smoothed over. A 2 MB photo commonly becomes a 6-10 MB PNG. If you want lossless and small, WebP in lossless mode sits between the two.

What does the optimisation level actually change?

Only the file size, never the pixels. Higher levels spend more processor time searching for a better lossless encoding: trying each of the five PNG row filters on every row, reducing the colour type where possible and repacking the compressed data. Level 6 typically finds 3-8% more than level 2 and takes several times longer.

Does the background become transparent automatically?

No. The JPG has no transparency information, so every pixel comes across fully opaque. The PNG can hold transparency, which is why this conversion is often a first step. Afterwards you can use a background removal tool to actually cut the subject out.

Are EXIF data and GPS coordinates kept?

Only if you turn on "Keep EXIF metadata". By default they are dropped, which is what most people publishing an image want. When the option is on, the camera block is repacked into the PNG's eXIf chunk and travels with the file, GPS coordinates included, so turn it on deliberately.

What is a palette PNG?

A PNG that stores a table of up to 256 colours and then one small index per pixel instead of full colour values. Diagrams, logos and interface screenshots almost always fit, and the file gets several times smaller with no change to a single pixel. The automatic colour type setting picks this whenever it is possible losslessly.

How many files can I convert at once?

Up to 100 files, 500 MB combined, with one set of settings applied to all of them. They come back as a single ZIP named pulsarkit-jpg-to-png.zip. If one file is damaged and fails, the rest of the batch still completes.

Does the file get uploaded to a server?

No. Decoding, encoding and optimisation all happen in your browser using WebAssembly. Nothing leaves the machine, no account is needed, and there is no copy to delete afterwards.