Convert BMP to PNG free in your browser. Batch convert, set the quality and download instantly. Your images are never uploaded.
Add your BMP files, adjust the settings and download PNG files. Everything runs in your browser, so your images are never uploaded.
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To convert BMP to PNG online, add your BMP files above, press Convert and download the PNG files. PNG is lossless, so every pixel is kept, while files are usually much smaller than uncompressed BMP. Nothing is uploaded; it all runs in your browser.
Convert BMP files to PNG to keep every pixel exactly while cutting file size. PNG is lossless, widely supported and works well on the web. It is a free tool from Websolindia, a New Delhi website design and SEO company that builds fast, image-optimised websites.
Unlike most online converters, this tool does not upload your images. Your browser decodes each BMP file, converts it and creates the PNG file on your own device. That keeps private photos private, avoids upload waits and keeps working on a slow connection once the page has loaded. You can convert up to 50 files at a time and download them one by one or together as a ZIP.
Working with BMP files more often? Our BMP to JPG Converter Online is another quick option. You may also like the JPG to PNG Converter Online, or browse every tool in the Websolindia image converter collection. Optimised images help page speed, which you can measure with our Website Performance Analyzer.
This table compares the two formats so you can decide whether converting is the right move.
| Feature | BMP | PNG |
|---|---|---|
| Full name | BMP (Windows Bitmap) | PNG (Portable Network Graphics) |
| Origin | Microsoft's Windows bitmap format | W3C Recommendation in 1996 |
| Compression | Usually none (uncompressed) | Lossless |
| Transparency | Only in some 32-bit variants | Yes, full alpha (256 levels of transparency) |
| Animation | No | No (animated PNG is a separate extension) |
| Colour depth | 1 to 32 bits per pixel | Up to 16 bits per channel |
| Typical file size | Very large | Large for photos, small for flat graphics |
| Best for | Legacy Windows software and raw scans | Logos, screenshots, graphics and anything needing transparency |
| Browser support | Browsers can show it, but it is rarely used on the web | Every browser, app and device |
| File extension | .bmp, .dib | .png |
File size: PNG is lossless and usually much smaller than uncompressed BMP, especially for screenshots and graphics.
This is exactly what happens to your file. Nothing is hidden, and you can verify that nothing is uploaded by watching your browser's network tab while you convert.
| Step | What happens |
|---|---|
| 1. Read the file locally | Your browser reads the file from your device into memory. Nothing is sent to a server. |
| 2. Identify the format | We check the file's first bytes (its signature) instead of trusting the extension, so a PNG renamed to .jpg is still handled correctly. |
| 3. Decode the BMP to pixels | The image is decoded to raw red, green, blue and alpha pixels using your browser's built-in BMP decoder. |
| 4. Resize (optional) | If you set a maximum width, larger images are scaled down with an area-weighted filter. Images are never enlarged, and the proportions are always kept. |
| 5. Keep transparency | Transparency passes straight into the PNG file, because PNG supports it. |
| 6. Encode the PNG | The pixels are written out as PNG using your browser's PNG encoder (lossless). Metadata such as camera details and location is not copied. |
| 7. Report the result | We show the dimensions, the sizes before and after, and the change: (new size − original size) ÷ original size × 100. For example, 500 KB becoming 350 KB is −30%. |
| Setting | Default | Range | What it does |
|---|---|---|---|
| Maximum width | None | 1–20,000 px | Scales larger images down. Never enlarges. |
| What | Formula | Notes |
|---|---|---|
| Size change | (new − original) ÷ original × 100 | Shown for every file. Negative means smaller. |
| Downscale factor | min(1, maximum width ÷ width) | Applied only when you set a maximum width; never above 1. |
Speed depends on your device and the image size. In our Chrome tests on a desktop-class processor, a 6-megapixel photograph took about 2 seconds to convert to WebP or PNG. AVIF is the slowest: about 2.5 seconds on Fast and about 7.5 seconds on Balanced. Phones and older laptops take longer, and images over about 120 megapixels are declined rather than risking a frozen browser.
| Format | Where it opens | Typical use |
|---|---|---|
| BMP | Browsers can show it, but it is rarely used on the web | Legacy Windows software and raw scans |
| PNG | Every browser, app and device | Logos, screenshots, graphics and anything needing transparency |
| This converter | Current Chrome, Edge, Firefox and Safari. Needs JavaScript | Private conversion on your own device |
Yes. PNG stores the BMP's pixels exactly, only compressing them without losing information.
BMP is usually uncompressed, so PNG is typically much smaller, especially for screenshots and graphics with large areas of flat colour.
Choose PNG for graphics, screenshots and anything that must stay exact. Choose the BMP to JPG Converter Online for photographs where the smallest file matters most.
Yes. Browsers decode common BMP variants and the converter re-encodes them as standard PNG.
No. Colours are preserved at standard 8-bit precision.
Yes. For web use, convert the PNG onward with the PNG to WebP Converter Online or the PNG to AVIF Converter Online.
Yes. It is free, needs no sign-up, adds no watermark and has no daily limit. You can convert up to 50 BMP files in one go. It is provided by Websolindia.
No. Your BMP files are read and converted inside your browser, on your own device. They are never sent to Websolindia or anyone else, which is why this converter is safe for private photos and documents.
Yes. The new file is created from the decoded pixels, so camera details, GPS location and other embedded metadata are not copied. If you need to keep metadata, use a desktop editor.
Up to 50 files per batch and 150 MB per file. Images above roughly 120 megapixels are declined with a clear message rather than freezing your browser.
Current versions of Chrome, Edge, Firefox and Safari.
Websolindia built it. We are a New Delhi website design, SEO and digital marketing company serving businesses since 2014. We also build fast websites with properly optimised images; see our website designing and SEO services.
All converters: Websolindia Image Converter
