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Convert PNG to JPG

Convert PNG images to JPG free, with no watermark and no daily limit. Pick the quality and the colour that replaces transparency. Nothing is uploaded.

Drop files here (up to 50)

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Preview

Choose an image and the result appears here as you change the options.

Shows the framing and the colour that replaces transparency. Compression quality is not simulated.

Options
%

Below about 75 the blocky artefacts around sharp edges become visible.

#ffffff

JPEG has no transparency. Transparent pixels are filled with this colour.

Results appear here. Nothing is uploaded.

    How it works

    Your PNG is decoded with the browser's own createImageBitmap, drawn onto an OffscreenCanvas inside a Web Worker, and re-encoded as JPEG by the same encoder your browser uses to save images. Because JPEG has no alpha channel, the canvas is first flooded with your chosen background colour and the image is composited on top of it. No wasm module is downloaded for this tool at all, which is why the conversion starts the instant you drop a file.

    Measured results

    These figures come from running this exact tool over a fixed set of sample files on every build, not from an estimate.

    Sample fileSettingsBeforeAfterChange
    logo-transparent.pngquality 8519 KB12 KB−34%
    photo-gradient.pngquality 853.36 MB305 KB−91%
    screenshot-text.pngquality 85219 KB136 KB−38%
    logo-transparent.pngquality 6019 KB9 KB−55%
    photo-gradient.pngquality 603.36 MB106 KB−97%
    screenshot-text.pngquality 60219 KB92 KB−58%

    Benchmark run 2026-08-02.

    What to watch out for

    Transparency is destroyed, not preserved

    JPEG cannot store an alpha channel. Every transparent pixel becomes the background colour you picked, which is why a logo with a transparent edge gets a visible white box around it on a coloured page.

    Text and line art get worse, not smaller

    JPEG's discrete cosine transform is built for photographs. On screenshots, diagrams and text it produces ringing around every sharp edge while often saving less space than PNG already did.

    Colour profiles are dropped

    The canvas pipeline converts to sRGB, so a wide-gamut PNG tagged Display P3 will come back with slightly duller saturated colours. For photographs destined for the web this is usually what you want anyway.

    Limits

    Files up to about 50 MB work reliably. Beyond that, the ceiling is your device's memory rather than any rule we impose — the work happens on your own machine. Tested in Chrome 140, Firefox 143, Safari 18.

    When converting PNG to JPG is the right call

    PNG stores every pixel exactly as it was. That is why a screenshot saved as PNG looks perfect and why a photograph saved as PNG is enormous — a 12-megapixel camera shot can easily reach 25 MB as a PNG and around 3 MB as a JPEG at quality 85, with no difference most people can see.

    So the decision is really about what is in the picture. Photographs, with their smooth gradients and noise, are what JPEG was designed for and they compress dramatically. Screenshots, logos, diagrams and anything containing text are the opposite case: PNG’s per-row prediction handles large flat areas of identical colour extremely well, while JPEG breaks the image into 8×8 blocks and leaves faint halos around every letter.

    The transparency problem, in plain terms

    This is the one thing that surprises people. A PNG can mark pixels as partly or fully see-through, which is how logos sit cleanly on any background. JPEG has no mechanism for this at all.

    Something has to fill those pixels, so this tool lets you choose what. White is the sensible default because most pages are white. If you know the logo will sit on a dark header, set the background to that exact colour and the edge will disappear. If you need the transparency itself to survive, JPEG is simply the wrong destination — keep the PNG, or convert to WebP, which is both compressed and alpha-capable.

    Why this runs on your own machine

    Every conversion here happens in a Web Worker in your browser. The practical consequences are worth stating plainly: your images are never transmitted, there is no queue to wait in, batch size is limited by your own memory rather than an upload cap, and the tool keeps working if your connection drops mid-session.

    Your files never leave your browser. Last updated 2026-07-31.