Crop BMP Image Online
Crop BMP images online and turn the bulky file into a tidy PNG. Lock a ratio, scale down, and download free—private, no upload.
How to Crop a BMP Online for Free
Trim any BMP in three easy steps: add your file, draw or lock the crop frame, and save a tidy PNG—no software needed.
Step 1
Upload Your BMP
Step 1. Drop a BMP file from your device into the tool and the crop box appears right away.
Step 2
Frame the Crop
Step 2. Drag the box freely or lock a ratio, then set Max Width to scale the result down.
Step 3
Download Result
Step 3. Click Crop, preview the trimmed image, and download it straight to your device.
Crop Huge BMP Files Into Tidy PNGs
BMP is one of the oldest image formats still in use, and it shows in the file size. Because BMP stores pixels with little to no compression, a single photo can balloon to tens of megabytes, making it painfully slow to email, upload, or embed on the web. You usually meet BMPs when exporting from legacy software, scanners, or specialized hardware that defaults to the raw format. The good news is that BMP’s bulk is almost entirely waste, and cropping it into a modern format recovers the same picture at a tiny fraction of the size without desktop software. Modern workflows rarely need raw BMP, so turning it into a compact image is almost always the right call for speed.
UnoIMG’s free BMP cropper turns that heavy file into a lean image in seconds. Drop your BMP and a draggable box appears; move it, resize from any corner, or lock a preset ratio such as 1:1 or 16:9. Because a canvas cannot keep the BMP format, the crop is saved automatically as a PNG—a compact, web-ready image instead of the bulky original. A Max Width field shrinks the result further for sharing, and because the crop uses the image’s real pixels, the output dimensions are always exact. Everything runs privately in your browser with no upload.
The savings show up wherever BMPs appear. Office teams trim scanned documents and screenshots so they email instantly; developers convert raw assets into compact web graphics; designers modernize legacy files for today’s platforms. E-commerce stores turn bulky product captures into fast-loading listings, and agencies prepare client deliverables that arrive quickly over any connection. Teachers crop worksheet scans for lesson packs, and researchers shrink lab captures for quick sharing. Archivists crop scanned records for fast retrieval. Each result downloads on its own, so you can refine several files in one sitting and keep every version visible on screen.
Best of all, the process is private and free. Cropping runs entirely in your browser, so your BMPs are never uploaded to a server or stored anywhere—nothing leaves your device, which keeps sensitive files fully on your machine. There is no watermark, no account, and no desktop software to install. Whether you keep the auto PNG or switch to JPG or WEBP, UnoIMG fits naturally into any daily routine, helping you frame a lighter, faster image in just a few seconds. The bulky original stays on your device, and only the lean cropped image is what you take away.
Crop to Size
Drag the box or lock a ratio to cut exactly the frame you need from the BMP.
Aspect Presets
Pick 1:1, 4:3, 16:9, 3:4, or 9:16 for documents, thumbnails, and screens.
Exports as PNG
Because BMP can't be kept, the crop is saved as a compact PNG automatically.
Scale Down
Set a Max Width to shrink the crop for faster web and email sharing in one step.
Private & Free
Everything runs in your browser, never uploaded, with no watermark and no cost.
Exact Pixels
Crops use the image's real pixels, so the output dimensions are precise every time.
FAQ
Frequently Asked Questions
BMP stores pixels with little or no compression, so even a small photo can weigh megabytes. Cropping it into a PNG removes that wasted space while keeping the same picture you see.
It is saved as PNG automatically, because a canvas cannot keep the BMP format. You get a compact, web-ready image instead of the bulky original, and you can also pick JPG.
Cropping alone never blurs your pixels because it uses the image’s real resolution. The only change is the format switch to PNG, which stays lossless for the cropped region you keep.
Lock a preset ratio, then set Max Width to the longest edge you need, like 800 or 1024. The crop uses real pixels, so the exported dimensions are always exact.
Yes. Cropping runs entirely in your browser, so your BMPs are never uploaded to a server or stored anywhere at all. Nothing leaves your device, keeping your files fully private.
You can load files one after another, and each cropped result appears with its own download button on screen. There is no single ZIP, but every file is ready for you to grab.
No. Everything runs in your browser on any device, with no install and no upload needed. Open the page, drop a BMP, crop, and download—that is the entire workflow you need.
No. The crop is a fresh canvas export, so embedded metadata is not carried into the new file at all. This also keeps the result clean and free of old data.