Bulk BMP to PNG Converter: Lossless Output
Convert uncompressed BMP images to lossless PNG. Same pixel-perfect quality, 70–90% smaller files, and compatible with every image editor, design tool, print service, and platform on earth. PNG gives you everything BMP offers, perfect fidelity, full color, without the enormous raw file sizes.
Your images
0 images addedConvert BMP to PNG in 3 Steps
No account, no install, no queue. Drop your BMP files in and the PNG versions are ready to download.
- Step 1
Drop your images in
Drag files onto the page, click to browse, or drop in a ZIP and every supported image inside is pulled out. JPG, PNG, WebP, AVIF, HEIC, GIF and BMP all work, mixed together in the same batch.
- Step 2
Adjust if you want to
Choose your output format and drag the quality slider. That is the whole setup. Settings holds a KB target, resizing and batch renaming if you want them, and can stay closed if you do not.
- Step 3
Download your PNG files
Conversion starts on its own, so there is usually nothing to press. Batches over 40 wait for one click so nothing runs away with your machine. Download files one at a time or take the whole batch as a single ZIP.
Why Convert BMP to PNG?
BMP and PNG share an important property: both are lossless. Every pixel is preserved exactly without any compression artifacts. The critical difference is that BMP achieves this by storing raw, uncompressed data, while PNG applies lossless compression to store the same information far more efficiently. Converting BMP to PNG typically reduces file size by 70–90% with absolutely zero visual difference. You get the identical pixel data, in a format that opens everywhere, at a fraction of the storage cost. It's the rarest of all conversions: a free upgrade with no trade-offs whatsoever.
Windows Bitmap Format
BMP is a raw pixel storage format introduced with Windows 1.0. It applies no compression to image data. Every pixel is written directly to disk at full bit depth. This makes BMP files extremely large: a full-HD 1920×1080 image always weighs approximately 6 MB in BMP, regardless of the image's actual complexity. BMP exists today almost exclusively as a legacy Windows format for internal application use. It was never designed for sharing, web delivery, or cross-platform compatibility.
Portable Network Graphics
PNG was designed in 1996 as a modern, patent-free, lossless image format, and it immediately outclasses BMP on every dimension except raw simplicity. PNG's DEFLATE compression algorithm reduces file sizes by 70–90% compared to BMP while preserving every pixel with identical accuracy. Full alpha transparency support, universal compatibility with every editor and platform, and significantly better compression make PNG the obvious successor to BMP for any use case outside Windows-internal workflows.
Same Pixels. A Fraction of the Size.
BMP to PNG is the only conversion where you get smaller files and identical quality. Zero trade-offs. Convert your entire BMP library in bulk, privately, with no installation.
True Bulk Conversion
Convert 10 or 500+ BMP files to PNG in one batch. No file limits, though BMP files are large by design, so large batches involve more raw data than other format conversions.
100% Private & Secure
Client-side only. Your BMP files never leave your device. No server, no cloud, no third party sees your images at any point during conversion.
Pixel-Perfect Lossless Output
PNG is lossless. Every pixel from your BMP is reproduced exactly. The output is visually identical to the BMP source with no artifacts, no color shifts, and no softening of any kind. Only the storage method changes.
ZIP Upload & Download
Upload a ZIP of BMP files. Download all converted PNGs as a single ZIP. Essential for bulk legacy asset migrations where individual BMP files would be impractical to handle one by one.
Batch File Renaming
Set a custom prefix, separator, numbering, and.png extension. Preview the filename pattern before downloading. Particularly useful when dealing with auto-generated BMP filenames from Windows applications.
the maximum size option
PNG is lossless, so target KB is not applicable. PNG file size is determined entirely by image content and cannot be tuned. For size-controlled output from BMP, try BMP to WebP or BMP to JPEG instead.
Works on Every Device
Windows, Mac, Linux, Chromebook, iPhone, Android. Any modern browser runs the conversion. Move BMP content to the universally compatible PNG format without needing Windows software.
Selective Processing
Upload a batch of BMP files and select only the specific images you need as PNG. Only those are converted and downloaded. No pre-filtering required before uploading your collection.
Full Transparency Preserved
32-bit BMP files with an alpha channel have their transparency preserved exactly in the PNG output. PNG's full alpha channel support handles this natively and without any manual configuration needed.
How SmallerImages Compares
Here's how our free BMP to PNG converter stacks up against typical online tools.
| Feature | SmallerImages | Typical Converter |
|---|---|---|
| Bulk conversion (200+ files) | Yes | No 10–20 file limit |
| Browser-based (no server uploads) | Yes | No Files uploaded to server |
| Lossless PNG output guaranteed | Yes | Varies. Some re-compress output |
| Full transparency preserved | Yes | Varies. May drop alpha channel |
| ZIP file upload & download | Yes | No |
| Batch file renaming | Yes | No |
| Before/after comparison | Yes | No |
| Selective processing | Yes | No |
| 100% free, no signup | Yes | Freemium / ads |
| Ad-free | Yes | No |
When You Need BMP to PNG
BMP to PNG is the go-to conversion when you need lossless quality, universal compatibility, and dramatically smaller files. With zero trade-offs between the three.
Editing BMP Images in Design Tools
Photoshop, GIMP, Affinity Photo, Figma, and every other image editing tool opens PNG immediately without any format concerns. While most editors do support BMP, PNG is the expected import format for professional editing workflows. Smaller, faster to load, and compatible with every feature including transparency compositing.
Long-Term Lossless Archiving
If you need to archive BMP images for long-term storage without any quality loss, PNG is the significantly more practical choice. PNG achieves the same pixel-perfect fidelity as BMP at 70–90% smaller file sizes. Meaning your archive takes far less storage space with no reduction in the quality or accuracy of preserved content.
Print Services & Pre-Press
Print shops and pre-press workflows universally accept PNG as a lossless input format. BMP may technically work with some print software, but PNG is the professional standard. Smaller, more portable, and compatible with every RIP and pre-press application without any format-related friction.
Legacy Windows Asset Migration
Migrating a legacy Windows application's image assets from BMP to a modern format? PNG is the natural landing point when lossless quality is non-negotiable. For icons, UI graphics, diagrams, and documentation images that must remain pixel-perfect throughout any subsequent editing or republishing workflow.
Sharing & Cross-Platform Handoffs
BMP files are not reliably supported on macOS, Linux, iOS, or Android without additional software. PNG opens natively on every operating system and every device without exception. Converting BMP to PNG before sharing with colleagues, clients, or collaborators on non-Windows platforms eliminates any compatibility friction entirely.
Reducing Storage Without Sacrificing Quality
A folder of 100 BMP screenshots at 1920×1080 can easily exceed 600 MB. The same images as PNG typically fit under 60 MB. With literally no visual difference. For teams managing large volumes of BMP screen captures, diagrams, or exported graphics, batch converting to PNG is an immediate, zero-risk storage win.
Trusted for BMP to PNG Conversion
Real feedback from people converting BMP to PNG every week, from teams in the UK, US, India, Japan, Pakistan, the UAE and beyond.
Cut about 60% off our image payload converting BMP to PNG. No visible difference to customers, measurably faster pages.
Converted an entire archive of BMP images to PNG in an afternoon. The per-file status list meant I could see exactly which ones were done and which had been skipped, which matters when you are dealing with that volume.
Straightforward BMP to PNG conversion that does what it says. a single PNG can run to several megabytes, and that is exactly what I needed for our asset pipeline.
The comparison slider is what earned my trust. Being able to drag across the actual image and check the PNG output against the original BMP before downloading is not something the other free tools bother with.
The thing that sold me is that there is no upload. I opened devtools, converted twenty BMP files to PNG, and watched the network panel stay empty. That is a real privacy claim, not marketing copy.
Added some files mid-batch and the button changed to say it would only process the new ones. Little detail, but it means I am not reconverting work that is already done.
We had a paid Kraken.io account on the team budget purely for image conversion. This replaced it for the BMP and PNG work, which is most of what we were doing. Small win, but it adds up.
Works on my iPad, which I did not expect. I was on a train, needed PNG versions of a handful of BMP files, and it just worked in Safari.
Being able to upload a ZIP and download a ZIP is what makes this usable for real work. I am not selecting 200 BMP files by hand and I am definitely not downloading 200 PNG files one at a time.
The interface tells you what is actually happening, which file, what state, why something was skipped. That sounds basic but almost nothing else in this space does it.
Faster than uploading would have been. Because it runs on my machine there is no waiting for a server queue. The BMP files convert as fast as my laptop can process them.
Our product pages were loading slowly on mobile and it was almost entirely image weight. Converting the BMP catalogue to PNG cut the total page size by more than half.
BMP to PNG Conversion and Compression Explained
What changes when you convert BMP to PNG, what it costs, and how to pick a quality setting you will not regret.
A BMP stores raw pixel data with no compression worth the name, which is why a 4000 pixel scan can run past 45 MB. Nothing about that helps you. Converting to PNG keeps the image and discards the waste, usually cutting the file to a tenth of its original size with no change you can see at normal viewing distance.
Both formats are lossy, so the conversion re-encodes rather than copies. Keep quality at 85 or above if the file is going to be edited again, and use the before and after slider to check the first image of a batch before you commit to the rest.
Set quality once and it applies to the whole batch, so a folder of two hundred files takes the same number of decisions as one. Everything runs on your own machine, so speed depends on your processor rather than on how busy a server is. If you are working to a hard limit, such as a content management system that rejects anything over 200 KB, open Settings and set a maximum file size instead of a quality percentage. The encoder then searches for the best quality that fits your budget, file by file.
All Formats. One Tool.
BMP to PNG is one of twenty-four conversion paths here, and each one has its own page with defaults already set for that pair. Whichever you land on, the tool behind it is the same: it accepts JPG, PNG, WebP, AVIF, HEIC, GIF and BMP, reads ZIP archives, and handles up to 500 images in a single batch.
Conversion runs in your browser using your own processor, so nothing is uploaded, nothing is queued behind other people, and there is no account, no watermark and no daily cap. Close the tab and the files are gone from memory; they were never anywhere else.
If you need a smaller file rather than a different format, the image compressor keeps your originals and works to a quality level or a size in kilobytes. To change dimensions, the image resizer handles fit, fill and crop, or stretch across a whole folder at once.
Frequently Asked Questions
Quick answers about converting BMP to PNG.
Is it safe to convert BMP to PNG on SmallerImages?
Is the PNG output truly lossless: identical to the BMP source?
How much smaller will PNG files be compared to BMP?
Does PNG preserve BMP transparency?
When should I use BMP to PNG vs BMP to WebP?
Why not just keep the BMP files?
Can I also convert BMP to WebP, JPEG, or AVIF?
How many BMP files can I convert at once?
Is SmallerImages completely free?
Can I upload a ZIP of BMP files?
Same Pixels. 90% Less Storage. No Trade-Offs.
BMP to PNG is the only image conversion where you genuinely get something for nothing. Smaller files, universal compatibility, and identical pixel quality. Not approximately the same. Pixel-perfect identical. Convert your BMP library to PNG for free, privately, without uploading a single file.
Convert BMP to PNG Now