BrowserTools

BMP to PNG Converter

Compress bulky BMP bitmaps into PNG

By Guga — BrowserTools maintainer, Tbilisi, Georgia Updated 2026-09-04
Free Private No uploads
What is BMP to PNG Converter?

A bitmap stores raw, uncompressed pixels, so a 1920×1080 screenshot is roughly six megabytes before anything has been encoded. Converting to PNG runs those same pixels through DEFLATE, which collapses runs and repeats very effectively, and the result is visually identical — no quality setting, because nothing was discarded. The saving depends entirely on the picture: a screen capture of an interface compresses to a small fraction, while photographic content saved as a bitmap shrinks less and may land close to its original size. Only the plain uncompressed Windows bitmap forms that browsers decode are handled; unusual RLE-compressed variants are not something this can open.

Convert uncompressed BMP bitmap images into PNG files that keep every pixel but weigh far less. Batch conversion with instant download, processed entirely on your device.

Private BMP to PNG Converter In Your Browser

BMP to PNG Converter is processed locally with client-side JavaScript. Your files never touch a server, and there is no queue to wait in.

Step-by-Step

How to use BMP to PNG Converter

1

Drop BMP files into the Convert to PNG panel, with a ceiling of 50 per batch.

2

Leave the settings alone — PNG output shows no quality slider, because the encoder is lossless.

3

Review the size comparison printed under each converted bitmap.

4

Press Download for one file or Download all (N) as ZIP for the lot.

Key Capabilities
  • The picker is limited to image/bmp and .bmp files
  • Encodes losslessly, so there is no quality slider and no possibility of generation loss
  • Accepts 50 bitmaps per run and returns them as one ZIP download
  • Reports the source byte size beside the PNG result on every single file
Common Use Cases
  • A QA engineer receiving 6 MB screenshot files from a Windows tool that can only write BMP, and needing something a browser will load.
  • A developer checking whether a legacy Windows resource screenshot can drop into a web page without bloating it.
  • A systems student documenting raw bitmap output from an embedded target that emits no other format.
Clear Answers

Frequently Asked Questions

My BMP was huge and the PNG barely shrank. Is that normal?
For photographic content, yes. BMP stores raw pixels and PNG compresses them without loss, so a photo-like image with continuous tone has few long runs to collapse and the reduction is limited.
Does it handle colour depth like 8-bit indexed or 32-bit BMPs?
The browser decodes the bitmap and this tool re-encodes the resulting pixels into a standard full-colour PNG. Whatever depth the source used, the output is a normal 8-bit-per-channel PNG with alpha if the source had it.
What about compressed BMP variants?
The common run-length-encoded and OS/2 variants are outside what browsers decode, so those files will fail to load here. A BMP exported as 24-bit or 32-bit uncompressed will work.
Do you keep a copy of my files?
There is no copy to keep — the decode and re-encode both run in the browser tab and no request is made. The Network panel in DevTools stays empty throughout.