Compress BMP images — free, private, no upload

BMP is uncompressed — converting to PNG keeps every pixel identical at a fraction of the size.

    About compressing BMP

    BMP is the native Windows bitmap format from 1990. Pixels are usually stored uncompressed, so files are enormous — a 12-megapixel photo is ~36 MB as BMP versus ~3 MB as JPEG. It survives in legacy Windows software, scanners and embedded systems. Unless a specific tool demands BMP, converting to PNG (lossless) or JPEG (photos) saves 90%+ with nothing lost in practice.

    How to compress BMP

    1. 1Drop BMP files above — batches are fine, and nothing is uploaded.
    2. 2Compression is lossless by default. Optionally lower quality below 70 for palette-based lossy savings, or cap the max dimension to downscale.
    3. 3Watch each file’s size drop, then download individually or as a ZIP.

    BMP strengths & limitations

    Strengths

    • Dead simple, universally readable
    • No compression artifacts ever
    • Fast to write on old hardware

    Limitations

    • Massive file sizes (usually uncompressed)
    • No real transparency support in practice
    • No animation, poor metadata

    Frequently asked questions

    How does BMP compression work here?+

    BMP is uncompressed — converting to PNG keeps every pixel identical at a fraction of the size.

    What quality setting should I use for BMP?+

    BMP compression here is lossless by default — there is no quality trade-off. The slider only matters if you drop below 70, which enables lossy palette reduction.

    Is there a limit on file size or number of images?+

    No hard limits: processing runs on your own device, so the only constraint is your browser’s memory for truly gigantic images. Batch as many files as you want.

    Will compressing BMP remove metadata?+

    Yes. Output files are built from raw pixels, so EXIF data — GPS location, camera model, timestamps — is stripped. Orientation is baked into the pixels first so photos stay upright. This usually saves a few extra kilobytes too.

    Are my images uploaded anywhere?+

    No. The codecs run as WebAssembly in your browser; the page works offline once loaded. Files, previews and results all live in your device’s memory only.

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