How it works
- Drop your files in the zone above (or click it, or paste with Ctrl+V).
- They convert instantly, right in your browser — nothing is uploaded.
- Adjust quality or max width if needed; files reconvert automatically.
- Download files one by one, or everything at once as a ZIP.
About the formats
BMP
BMP is the uncompressed Windows bitmap format from the early 90s. Files are enormous — often 20–50× larger than an equivalent JPG — with no visual benefit for photos, so converting is almost always worthwhile.
PNG
PNG is the standard lossless format: perfect quality, full transparency support, and universal compatibility. Its weakness is size — photographs saved as PNG are often 5–10× heavier than a visually identical JPG or WebP.
What this conversion actually gives
Measured with the converter on this page, on a 2016 × 1512 px test image: the BMP file weighs 8.7 MB.
| Setting | Result | Change |
|---|---|---|
| Lossless (PNG ignores the quality slider) | 7.3 MB | −16 % |
| Max width 1600 px, quality 85 % | 4.4 MB | −50 % |
The file loses −16 % — enough for an attachment or a web page, with no visible change on screen.
Capping the width at 1600 px gives 4.4 MB — plenty for any screen.
- PNG is lossless: not a single pixel is altered.
Your own files will differ — a photo full of detail compresses less well than a flat graphic. These figures come from one reproducible test image, not from an average.
Frequently asked questions
How big will my PNG file be?
On our 2016 × 1512 px test image, a BMP of 8.7 MB comes out at 7.3 MB at the default quality (−16 %). Lower the quality slider or set a maximum width and the figure drops further — the page shows the new size as soon as the file is reconverted.
How much smaller will my BMP get?
Typically 95–98% smaller as JPG or WebP, and 50–80% smaller even as lossless PNG, because BMP applies no compression at all.
Will converting to PNG keep transparency and quality?
Yes. PNG is lossless, so no quality is lost, and it preserves transparent backgrounds — ideal for logos, screenshots and graphics with sharp edges. The trade-off is a larger file than JPG or WebP.
Are my files really private?
Yes. The conversion runs entirely in your browser using its built-in image engine. Your files are never uploaded, stored or seen by any server — you can even disconnect from the internet after the page loads and keep converting.
Is this free? Is there a file limit?
Completely free, no account, no watermark. Convert as many files as you like, up to 200 MB each — the only limit is your device's memory.
Can I convert many files at once?
Yes — drop a whole batch at once. Each file converts independently and you can grab everything in a single ZIP when done.