BMP to GIF Converter

Upload a BMP bitmap and download it as a GIF — converted entirely in your browser.

BMP → GIFBrowser basedNo uploadFree

Last updated: May 30, 2026

Drop a BMP file here or click to browse

Converted to GIF entirely in your browser

Colours are reduced to a 256-colour palette (median cut) because the GIF format supports at most 256 colours per frame.

Client-Side Processing

Input Data Stays on Device

Instant Local Execution

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What is BMP to GIF Converter?

BMP to GIF converts uncompressed Windows bitmap (.bmp) images into the GIF format. GIF uses a palette of up to 256 colours and lossless LZW compression, so the resulting file is usually far smaller than the original bitmap while staying crisp for graphics, icons, and flat-colour images.

This converter decodes your BMP with the browser's image engine, reduces the colours to a 256-entry palette using median-cut quantization, then builds a standard GIF89a file with LZW compression. Nothing is uploaded to a server.

How to Use BMP to GIF Converter

Drop a BMP file onto the upload area or click to browse

Wait a moment while the image is decoded and quantized

Preview the GIF result next to your original

Click Download to save the GIF

Common Use Cases

Shrinking large uncompressed BMP graphics into compact GIFs.
Converting flat-colour logos or icons from BMP to web-friendly GIF.
Preparing bitmap screenshots for sharing where GIF is required.
Turning legacy BMP assets into a more widely supported raster format.

Example Input and Output

A 1024x768 BMP screenshot of a flat-colour UI converts to a much smaller GIF with no visible quality loss.

Input

screenshot.bmp (2.3 MB, 24-bit bitmap)

Output

screenshot.gif (180 KB, 256-colour GIF)

How This Tool Works

The browser decodes the BMP to canvas pixels, median-cut quantization builds a ≤256-colour palette, the pixel indices are LZW-compressed, and a GIF89a file is assembled and offered for download.

Technical Stack

TypeScriptCanvas APIMedian-cut quantizationGIF89a LZW encoderClient-side processing

Colour reduction

Median-cut quantization picks a representative 256-colour palette. Images with fewer than 256 colours convert losslessly.

Privacy

The converter never sends your image to a server — everything happens in your browser tab.

Frequently Asked Questions

Is my BMP uploaded anywhere?

No. Decoding, colour quantization, and GIF encoding all run locally in your browser.

Why does the GIF look slightly different?

GIF supports at most 256 colours, so photo-like BMPs are reduced to a 256-colour palette. Flat-colour graphics usually convert with no visible change.

Does the GIF keep transparency?

This converter produces a flat (non-transparent) GIF. The bitmap is composited onto white before colour reduction.

What size of image can I convert?

Any size your browser can decode. Very large images take longer because quantization runs per pixel.