BMP Image Converter – Convert BMP to JPG, PNG, WebP, ICO & TIFF
About the BMP Image Converter
BMP stores images with essentially no compression. Every pixel occupies three or four bytes on disk, which means a single 1920×1080 bitmap runs to roughly 6MB — the same image as a JPG might be 200KB. That is the entire reason people convert BMP files, and it is why the size change figure on this tool comes back green almost every time.
Upload a BMP up to 10MB and this converter re-encodes it as JPG, PNG, WebP, AVIF, GIF, ICO, or TIFF, all inside your browser. The format is a holdover from early Windows, so BMP files still turn up from screen capture utilities, scanner software, medical and industrial imaging systems, and older applications that never added modern export options. Converting is usually the first step before the image can be emailed, uploaded, or published anywhere.
Which target you choose depends on what the image contains. JPG is the right answer for photographs and scans where a modest quality tradeoff buys an enormous size reduction. PNG suits screenshots, diagrams, and anything with text or flat color, since it compresses losslessly and keeps edges perfectly sharp. WebP and AVIF beat both on file size for web delivery, while ICO, GIF, and TIFF cover favicons, legacy embedding, and print work.
Some 32-bit BMP files carry an alpha channel. Where that transparency exists, PNG, WebP, AVIF, ICO, and TIFF preserve it. JPG and GIF cannot, so the converter fills the canvas white before drawing — transparent regions arrive white rather than black, which is the failure most tools get wrong.
The quality slider appears for JPG, WebP, and AVIF and stays hidden for the lossless formats where it would have no effect. Format support is tested against your own browser as the page loads, so any encoder your browser lacks is disabled rather than left to fail halfway through a conversion.
Resizing runs in the same pass, by percentage or exact pixels with an aspect ratio lock. Because bitmap dimensions and file size are directly proportional, halving the width and height cuts an uncompressed BMP to a quarter before any format compression is applied — the File Size Calculator makes that arithmetic concrete when you are working to a size budget.
Before publishing, BigToolSite’s own team ran 24-bit and 32-bit bitmaps, screen captures, and scanned documents through all seven outputs, and confirmed the reported size savings match the actual downloaded files rather than the in-memory canvas.
How to Use the BMP Image Converter
- Drop a BMP onto the upload panel or click to browse. The tool accepts .bmp files up to 10MB and rejects anything else with a specific message.
- Check the file card that appears — thumbnail, filename, file size, and pixel dimensions. That file size figure is usually the reason you are here.
- Choose an Output Format from the seven buttons. JPG is preselected as the most common destination, but PNG is better for screenshots and text-heavy images.
- Set the Quality slider when converting to JPG, WebP, or AVIF. It runs 1 to 100 and defaults to 85; it is hidden for PNG, GIF, ICO, and TIFF.
- Pick a Resize mode: Original Size, 25%, 50%, 200%, or Custom Size. Custom reveals width and height fields with Maintain aspect ratio enabled, so filling one calculates the other.
- For ICO output, select an ICO Size from 16 to 256 pixels. Icons are square, so this replaces the resize options.
- Press Convert & Download. The progress bar tracks each stage, the file saves automatically with a -converted suffix, and the before-and-after preview and statistics appear below.
- Use Reset or the Remove button to clear everything and convert another bitmap.
Example Usage
Input: scan.bmp, 1600×1200, 5.6 MB. Format JPG, Quality 85, Resize Original Size.
Output: scan-converted.jpg at roughly 240 KB — a size change near −96% in green, with no visible difference at normal viewing size. This single conversion is what makes an unmanageable scanner output emailable.
Input: screenshot.bmp, 1920×1080, 6.2 MB. Format PNG.
Output: screenshot-converted.png at perhaps 300 KB with every pixel preserved exactly. No quality slider appears because PNG is lossless. For screenshots this beats JPG outright — text and interface edges stay crisp instead of picking up compression halos.
Input: logo.bmp, 512×512, 1 MB. Format ICO, ICO Size 32×32.
Output: logo-converted.ico, a few kilobytes, ready to serve as a favicon. BMP and ICO are closely related formats internally, which is why bitmaps convert to icons so cleanly.
Input: product.bmp, 2400×1800. Format WebP, Quality 80, Resize 50%.
Output: product-converted.webp at 1200×900 and well under 100 KB. Combining the downscale with a modern codec compounds the savings — the resize cuts pixel count to a quarter before WebP compression is even applied. If you also need a PNG master of the same image, the PNG Image Converter handles the follow-on conversions from that point.
WebP is efficient enough that people often need to go back the other way for compatibility with older software. The WebP Image Converter covers that direction.
Frequently Asked Questions
BMP stores raw pixel data with no compression at all. A 24-bit bitmap uses three bytes per pixel, so file size is simply width multiplied by height multiplied by three. Modern formats apply compression and routinely land at a tenth to a fiftieth of that size.
Use JPG for photographs and scans, PNG for screenshots, diagrams, and anything containing text, and WebP or AVIF when the destination is a web page. All three cut the file size enormously compared with the original bitmap.
Some, since JPG is lossy. At quality 85 the loss is rarely visible in photographs, though sharp text and flat color areas can show artifacts. Convert to PNG instead when the image contains interface elements, line art, or lettering.
No. PNG is lossless, so the converted file contains exactly the same pixels as the bitmap — just stored efficiently. It is the safest choice when you need to preserve the image precisely while cutting file size.
32-bit BMP variants can carry an alpha channel, though many BMP files are 24-bit with no transparency at all. Where an alpha channel exists, choose PNG, WebP, AVIF, ICO, or TIFF to keep it; JPG and GIF will replace transparent areas with white.
Because BMP is uncompressed, the limit is reached at fairly modest dimensions — around 2000×1700 pixels for a 24-bit file. Resizing or converting the bitmap in an image editor first will bring it under the cap.
Rarely. It survives mainly in legacy Windows software, some capture utilities, and specialist imaging equipment where uncompressed output is required. For storage, sharing, or web use, PNG offers the same lossless fidelity at a fraction of the size.
No. The bitmap is decoded, redrawn, and re-encoded entirely in your browser, then returned as a download. Nothing is transmitted or stored anywhere.
Yes, it’s completely free with no signup required.
