🖼️

BMP to PNG Converter

Converting BMP to PNG replaces an uncompressed bitmap with a losslessly compressed image that's typically 50–80% smaller without losing a single pixel of quality. Unlike JPG conversion, BMP-to-PNG is completely lossless — the output is pixel-identical to the input, just stored more efficiently. PNG also adds support for transparency (alpha channel), which BMP handles inconsistently across applications. This conversion is ideal for screenshots, diagrams, text-heavy images, and any content with sharp edges where JPEG artifacts would be unacceptable. SublimePDF applies optimal PNG compression with configurable settings for the best file size reduction.

Convert BMP to PNG instantly in your browser — no file uploads, no registration, and completely free.

Drop your BMP files here

or click to browse — up to 50MB

How to Convert BMP to PNG Online

Upload your BMP file

Drag and drop your .bmp image. All BMP variants are supported: 1-bit monochrome, 4-bit and 8-bit indexed color, 24-bit RGB, and 32-bit RGBA.

Configure PNG output

Choose the color mode (RGB, RGBA with transparency, grayscale, or indexed color for smallest file size) and compression level (1–9, where 9 is maximum compression at slower speed).

Download your PNG

The output PNG is pixel-identical to the BMP input but 50–80% smaller. Transparency from 32-bit BMP files is properly preserved in the PNG alpha channel.

BMP to PNG Converter Features

100% lossless conversion — output is pixel-identical to the BMP input

50–80% file size reduction through efficient PNG compression

Full alpha channel transparency support from 32-bit BMP sources

Handles all BMP bit depths: 1-bit, 4-bit, 8-bit, 24-bit, and 32-bit

Configurable compression level (1–9) to balance speed and file size

Optional color mode optimization: indexed, grayscale, RGB, or RGBA

100% free — no registration required

Files processed in your browser (never uploaded)

When to Convert BMP to PNG

Convert BMP screenshots to PNG for lossless web hosting with transparency support
Replace BMP assets in legacy applications with smaller PNG files that maintain exact quality
Convert BMP scan outputs to PNG for space-efficient archival without any quality compromise
Prepare BMP diagrams and schematics as PNG for embedding in web pages and documentation
Convert 32-bit BMP files to PNG to standardize transparency handling across platforms

About BMP and PNG

What is BMP?

Bitmap Image (.bmp) — An uncompressed image format that preserves every pixel, resulting in large file sizes but perfect quality. Learn more about BMP →

What is PNG?

Portable Network Graphics (.png) — A lossless image format that supports transparency, ideal for graphics, logos, and screenshots. Learn more about PNG →

Privacy & Security

Your files never leave your device. All conversion happens locally in your browser using WebAssembly technology.

BMP to PNG Conversion FAQ

Is the conversion truly lossless?

Yes. PNG uses Deflate compression which is mathematically lossless. Every pixel in the output PNG is identical to the original BMP — there is zero quality loss.

When should I choose PNG over JPG?

Choose PNG for screenshots, text, line art, diagrams, and images with sharp edges or transparency. Choose JPG for photographs and images with complex smooth gradients where lossy compression is acceptable.

How is the alpha channel handled?

32-bit BMP files with an alpha channel are converted to RGBA PNG, preserving full transparency data. 24-bit BMP files produce RGB PNG without transparency.

Can I reduce file size further with indexed color mode?

Yes. For images with fewer than 256 unique colors (common with diagrams and icons), indexed color PNG can be 60–90% smaller than 24-bit PNG.

What's the difference in file size between BMP, PNG, and JPG?

For a typical 1920×1080 screenshot: BMP ≈ 6 MB, PNG ≈ 1–2 MB (lossless), JPG at quality 85 ≈ 200–400 KB (lossy). PNG gives you the best tradeoff when lossless quality is required.

Related Guides

How to Convert Scanned PDF to Text

Scanned PDFs are essentially images — you can't select or search the text. OCR (Optical Character Recognition) technology converts these image-based PDFs into searchable, editable text. SublimePDF's OCR tool handles this conversion right in your browser.

How to Convert JPG to PDF

Converting JPG images to PDF is useful for creating photo albums, digitizing receipts, compiling screenshots, or sharing images in a universally readable format.

How to Convert PDF To Grayscale

Printing color PDFs on black-and-white printers often produces muddy, hard-to-read output because the printer's automatic color conversion isn't optimized for clarity. Pre-converting your PDF to grayscale ensures consistent, clean results on any mono printer and can dramatically reduce printing costs for large jobs. SublimePDF converts all colors—in text, images, and vector graphics—to properly weighted grayscale.