BMP to PNG Converter

Converting BMP to PNG compresses the image losslessly, typically shrinking the file 2–5× while preserving every pixel exactly. PNG also handles alpha channels reliably where BMP's alpha support is inconsistent.

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Drag & drop image files here, or browse

Drop your BMP files here

What changes when you convert BMP to PNG

Lossless conversion. Pixels transfer exactly. File size drops substantially because PNG uses DEFLATE compression where BMP uses none. Alpha transparency becomes properly supported.

When to use this conversion

  • Replacing BMP assets in web projects with smaller PNGs that look identical
  • Archiving BMP source material in a space-efficient lossless format
  • Converting BMP screenshots for modern documentation or design workflows
  • Preparing BMP-sourced icons or UI art for cross-platform use

Where the output plays

PNG runs on every browser, OS, and image tool ever made.

About these formats

BMP (Windows Bitmap)

BMP is the uncompressed Windows bitmap format from 1990. Files are huge because almost nothing is compressed, but the format is trivial to decode and supported by virtually every Windows utility, embedded system, and legacy tool. Useful as an interchange format when other options fail.

PNG (Portable Network Graphics)

PNG is a lossless image format designed to replace GIF. It uses DEFLATE compression, supports an 8-bit alpha channel for full transparency, and preserves every pixel exactly. PNG excels at images with sharp edges, large flat-color regions, text, UI screenshots, and anything you'll re-edit.

How It Works

  1. Add your BMP files Drag BMP images onto the page or click to pick them from your file browser. Batch uploads are fine.
  2. Choose PNG settings Pick quality or compression settings for the PNG output. Defaults match common target use cases.
  3. Convert in your browser The converter runs locally via WebAssembly. Nothing uploads. Progress shows per file so you know exactly what's happening.
  4. Download PNG files Grab each converted file individually, or download the whole batch as a single ZIP.

Features

Supported Formats

FAQ

How much smaller is PNG than BMP?

Typically 2–5× smaller. For images with flat-color regions (screenshots, UI, logos) the compression is very effective; for noisy photographic content, less so.

Will alpha transparency survive?

Yes, if the BMP had an alpha channel (32-bit BMP). PNG's alpha support is more reliable than BMP's and the transparency transfers cleanly.

What is BMP (Windows Bitmap)?

BMP is the uncompressed Windows bitmap format from 1990. Files are huge because almost nothing is compressed, but the format is trivial to decode and supported by virtually every Windows utility, embedded system, and legacy tool. Useful as an interchange format when other options fail.

What is PNG (Portable Network Graphics)?

PNG is a lossless image format designed to replace GIF. It uses DEFLATE compression, supports an 8-bit alpha channel for full transparency, and preserves every pixel exactly. PNG excels at images with sharp edges, large flat-color regions, text, UI screenshots, and anything you'll re-edit.

Are my files private?

Yes. The converter runs entirely in your browser using WebAssembly. Your images are never uploaded, never sent to a server, and never leave your device.

Is there a file size limit?

There's no hard limit, but because everything runs in your browser you're bounded by available memory. Very large images (over a few hundred megapixels) can hit browser memory limits. Process in smaller batches if you run into issues.