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Convert BMP to PNG Online Free — Fast Batch Conversion
How to Convert Images Online
1Upload your BMP file
Click the upload button or drag and drop your BMP file.
2Convert
Click Convert. Convertify processes your file instantly.
3Download PNG
Download your converted PNG file.
Supported Image Formats
PNG
Lossless format that preserves every pixel. Best for screenshots and logos.
BMP
Uncompressed bitmap format. Maximum quality but very large file size.
HEIC
Apple photo format used by iPhone and iPad. High quality with small file size.
HEIF
High Efficiency Image Format — same as HEIC, used on Apple devices.
WebP
Modern image format by Google. Up to 30% smaller than JPG with the same quality.
JPG
Universal format for photos. Supported everywhere, great balance between quality and file size.
GIF
Classic format for simple animations. Supports transparency and up to 256 colors.
TIFF
Professional lossless format used in printing and photography.
AVIF
Next-gen format with excellent compression. Up to 50% smaller than JPG.
PPM
Portable Pixmap format used in Unix/Linux environments.
HDR
High Dynamic Range format storing extended brightness data.
FITS
Flexible Image Transport System used in astronomy and science.
PDF
Portable Document Format. Convert PDF pages to JPG, PNG or WebP images.
AVIF vs WebP vs HEIC vs JPG
Quick comparison to help you choose the right format
AVIF
- Size: Up to 50% smaller than JPG
- Browsers: Chrome, Firefox, Safari
- Transparency: ✓
- Best for: Web performance
WebP
- Size: 25-35% smaller than JPG
- Browsers: All modern browsers
- Transparency: ✓
- Best for: Web compatibility
HEIC
- Size: ~50% smaller than JPG
- Browsers: Safari only
- Transparency: ✓
- Best for: iPhone storage
JPG
- Size: Baseline
- Browsers: All browsers & apps
- Transparency: ✗
- Best for: Universal sharing
Frequently Asked Questions
- Will I lose quality converting BMP to PNG?
- No. Both BMP and PNG are lossless formats. Zero quality loss during conversion.
- How much smaller will my PNG be compared to BMP?
- Typically 5-10x smaller with zero quality loss, depending on image content.
- Does PNG support transparency?
- Yes. PNG supports full alpha channel transparency. BMP has very limited transparency support.
- Can I convert multiple BMP files at once?
- Yes. Convertify supports batch conversion.
Why convert BMP to PNG?
BMP stores every pixel as raw uncompressed data — a 1920×1080 image at 24-bit color is exactly 5.93 MB regardless of what the image looks like. PNG uses lossless DEFLATE compression and typically reduces that to 500 KB–2 MB with zero quality loss. PNG also supports a full 8-bit alpha channel for transparency, which BMP handles unreliably. Every browser, CMS, and social platform supports PNG natively — Discord, Instagram, Twitter and WhatsApp do not render BMP inline at all.
BMP vs PNG — complete comparison
| Feature | BMP | PNG |
|---|---|---|
| Compression | None (BI_RGB) | Lossless DEFLATE |
| File size at 1080p | ~5.93 MB | 500 KB – 2 MB |
| Transparency | Unreliable (V4/V5 only) | Full 8-bit alpha |
| Browser support | Limited | Universal |
| Web use | Not recommended | Standard |
| Color depth | 1–32 bit | 1–48 bit |
| Year introduced | 1985 | 1996 |
| Discord / Instagram | No inline preview | Fully supported |
Real file size examples
At 640×480 a 24-bit BMP is around 900 KB — PNG of the same image runs 50–300 KB, a 3–18× reduction. At Full HD 1920×1080, BMP is exactly 5.93 MB (formula: 5760 bytes per row × 1080 rows + 54 byte header). The same image as PNG is typically 500 KB–2 MB depending on content. At 4K 3840×2160, BMP hits 23.7 MB while PNG stays at 1.5–8 MB. Images with large solid areas compress most aggressively — a Windows screenshot compresses far better than a photograph.
Does converting BMP to PNG lose quality?
No. Both BMP and PNG are lossless formats. Every single pixel is preserved exactly during conversion. The file gets smaller purely because PNG applies DEFLATE compression — a combination of LZ77 sliding-window matching and Huffman coding — without discarding any data. This is fundamentally different from converting to JPG or WebP lossy, which permanently discard information to achieve smaller sizes. You can convert BMP to PNG and back to BMP and the result will be bit-for-bit identical to the original.
PNG-8 vs PNG-24 vs PNG-32 — which to choose
PNG-8 stores up to 256 colors in an indexed palette with optional 1-bit transparency — ideal for logos, icons and simple graphics where file size matters most. PNG-24 stores full truecolor RGB without an alpha channel — the right choice for screenshots, illustrations and images without transparency. PNG-32 adds a full 8-bit alpha channel giving 256 levels of transparency per pixel — the only correct format for logos, UI elements and images with soft or semi-transparent edges. When converting from BMP, PNG-24 or PNG-32 is almost always the right output.
Does BMP actually support transparency?
Technically yes — BITMAPV4HEADER (Windows 95) added an AlphaMask field and BITMAPV5HEADER (Windows 98/2000) formalized full alpha channel support. Photoshop from v7 onwards, GIMP and Chrome can write and read 32-bit BMP with alpha. In practice though, transparency in BMP is unreliable. Legacy code expecting the standard 40-byte BITMAPINFOHEADER ignores the alpha byte entirely and treats it as padding. Many tools produce inconsistent results. PNG with its tRNS chunk (for indexed) or color type 6 RGBA provides universally consistent, predictable transparency across every application and browser.
Who converts BMP to PNG — real use cases
Windows users receive BMP files from legacy scanners, old corporate software or colleagues using Windows XP-era Paint which saved BMP by default. Game developers migrate assets from RPG Maker 2000/2003 (which requires BMP) to modern engines like Godot or Unity. Retro modders working on Fallout Tactics or RollerCoaster Tycoon 3 convert BMP screenshots to PNG for forum uploads. Windows developers extract resources from .ico and .cur files which embed BMP internally. Medical professionals export DICOM images via dcmj2pnm as BMP for certified workflows then convert to PNG for sharing. Embedded engineers convert STM32/AutoCAD BMP outputs to PNG for documentation. Discord and social media users hit the BMP wall — Discord has had no inline BMP preview since 2020, Instagram and Twitter reject BMP entirely.
How to convert BMP to PNG on any platform
On Windows 10 and 11 open the BMP in Paint, go to File → Save As → PNG. On macOS open in Preview, File → Export → PNG. In Photoshop use File → Save As → PNG. In GIMP use File → Export As → PNG. From the command line with ImageMagick: magick input.bmp output.png or for batch conversion magick *.bmp -set filename:f %t %[filename:f].png. In Python with Pillow: from PIL import Image; Image.open(file.bmp).save(file.png). Convertify handles batch conversion of up to 10 BMP files simultaneously without installing any software.
Understanding the BMP format
BMP (Bitmap, Device-Independent Bitmap) was introduced by Microsoft in November 1985 as a direct memory dump format for the Windows GDI subsystem. The file begins with a 14-byte BITMAPFILEHEADER starting with magic bytes 0x42 0x4D (the letters BM), followed by a DIB header in one of seven documented variants ranging from 12 bytes (BITMAPCOREHEADER, Windows 2.x) to 124 bytes (BITMAPV5HEADER, Windows 98/2000 with ICC color profile support). Pixel rows are stored bottom-up by default and padded to 4-byte boundaries. Supported color depths are 1, 4, 8, 16, 24 and 32-bit. Compression via BI_RGB (none), RLE4 or RLE8 is possible but compression is almost never used in practice. The Windows clipboard uses CF_DIB/CF_DIBV5 internally — when you copy an image in any Windows application it is stored as BMP in memory.
Privacy and security
Your BMP files are uploaded over HTTPS, converted on our server using Rust and libvips, and automatically deleted after download. No files are stored permanently. No account or signup is required. Convertify processes files in isolated temporary storage and does not use your images for any other purpose.