Skip to main content
FormatDrop
Home›Image›BMP to PNG
BMP
→
PNG

BMP to PNG Converter — Free, Lossless, No Upload

Shrink Windows BMP images into PNG with every pixel kept exactly — converted on your device, never uploaded.

Free · no signup2 free files a day100% in-browser · no upload

Tap to select BMP files

or click to browse

2 free files per day (2 left today) · Up to 10 MB each · Upgrade for more

Free image outputs include a repeating formatdrop.com watermark · Remove with Pro

✓ Files never uploaded✓ 100% browser-based✓ No account required
Need the reverse?PNG → BMP

How to convert BMP to PNG online

  1. 1

    Drop your BMP file

    Drag your Bitmap Image File file onto the box above, or click it to pick a file.

  2. 2

    Wait a few seconds

    Conversion starts on its own and runs on your device, not on a server.

  3. 3

    Download your PNG

    Click Download to save the Portable Network Graphics file.

BMP vs PNG: format overview

BMP

Bitmap Image File

Microsoft · 1987

Compression
none
Transparency
No
  • ✓ No compression — original pixel data preserved
  • ✓ Universal Windows support
  • ✗ No compression = massive files
PNG

Portable Network Graphics

PNG Development Group (Thomas Boutell) · 1996

Compression
lossless
Color depth
16-bit
Transparency
Yes
  • ✓ Lossless compression — pixel-perfect quality
  • ✓ Full alpha transparency (8-bit alpha channel)

BMP magic bytes: 42 4D

PNG magic bytes: 89 50 4E 47 0D 0A 1A 0A

Why convert BMP to PNG?

BMP (bitmap) is an old Windows image format. Most BMP files store every pixel with no compression at all, so even a simple picture takes a lot of space. They come from Paint, older scanners and screenshot tools, and from legacy software and games.

PNG is lossless too, but it compresses. You get exactly the same picture in a much smaller file, and a format every website, app, chat and email client accepts. Many upload forms don't take .bmp at all.

If the file is a photo and you need it as small as possible, BMP to JPG makes a far smaller file, but JPG is lossy. Choose PNG when the picture must stay exact: screenshots, diagrams, icons, pixel art and scans of text.

Common reasons to convert BMP to PNG:

  • ›Uploading to a website or app that doesn't accept BMP
  • ›Making old Paint images or scans small enough to email
  • ›Keeping screenshots and graphics exact while saving space
  • ›Archiving legacy images in a format that will stay readable

Quality & file size: BMP to PNG

Every pixel stays exactly the same — we checked our test files pixel by pixel against the original BMPs.

How much smaller the PNG is depends on the picture. A 1920×1280 photo stored as a 7.37 MB BMP became a 4.66 MB PNG (37% smaller) in about 2 seconds. A simple 800×600 graphic of 1.92 MB became 11.8 KB — over 99% smaller. Flat colours, text and screenshots compress the most.

32-bit BMPs with transparency keep it: the PNG has the same see-through areas. Ordinary 24-bit BMPs have no transparency, so their PNGs are plain RGB images, which keeps them as small as possible.

On the free tier the PNG gets a repeating formatdrop.com watermark, and the extra detail makes it larger; Pro output has none.

Frequently asked questions

What is a BMP file?
A bitmap image, a format from early Windows that usually stores every pixel uncompressed. That makes BMP files simple but very large, and many websites and apps don't accept them.
Does converting BMP to PNG lose quality?
No. PNG is lossless, so every pixel is kept exactly. We checked our test conversions pixel by pixel against the original BMPs.
How much smaller will the PNG be?
It depends on the image. In our tests a photo shrank by 37% and a simple graphic by over 99%. Screenshots, text and flat colours shrink the most.
Does BMP to PNG keep transparency?
Yes, if the BMP has it. 32-bit BMPs with an alpha channel keep their transparent areas in the PNG. Most BMPs are 24-bit and have none.
Should I convert BMP to PNG or JPG?
PNG keeps the picture exact and suits screenshots, graphics and text. JPG makes photos much smaller but loses a little detail. For photos you'll only share, JPG is often fine.

Your BMP file never leaves this tab — FormatDrop has no endpoint that receives file data. How it works