ImgSquash

BMP to JPG Converter

BMP is uncompressed — files are enormous for no visual benefit. Converting to JPEG gives you small files that open everywhere — every browser, phone, editor and printer. The size is the entire issue — email attachment limits, upload caps and disk space all bite long before quality does. Common BMP variants also carry no alpha channel, so there is no transparency to lose, and none to gain by staying put. Photographs headed somewhere you do not control: an email attachment, a form upload, a print order, a document, or anyone else's computer. Drop your files below and the conversion runs here, in this tab, through the Canvas API — nothing is uploaded, so there is no size cap, no watermark and no sign-up. Pick a quality level before you convert: 80% is the usual sweet spot, and dropping below about 60% starts to show around hard edges and in flat areas of sky.

Drop images here

or click to browse — JPG, PNG, WebP, HEIC, AVIF, GIF, BMP, SVG

Private: files never leave your device

What a BMP file actually is

BMP is Microsoft's original raster format and in normal use stores pixels with no compression at all: three bytes per pixel, plus a header. A 12-megapixel photo lands around 36 MB. An optional run-length mode exists but is rarely produced.

BMPs turn up from legacy Windows software, older scanner drivers, industrial and medical equipment, and Paint on an ancient machine. New files in this format are almost always a sign that something in the chain has not been updated in a long time.

What you get from JPG

Saving as JPEG re-encodes the image with lossy DCT compression at a quality level you choose. Around 80% is the usual sweet spot: files shrink dramatically and the difference is invisible at normal viewing sizes.

Nothing in mainstream computing fails to open a JPEG. Thirty-year-old software, print shops, hospital systems, government upload forms, every phone and every browser — if a system takes images at all, it takes JPG.

What changes when you convert BMP to JPG

This is where the file size actually drops. A BMP stores its image without discarding anything; JPEG works in 8×8 blocks and throws away the fine detail inside each one, then usually halves the colour resolution as well through chroma subsampling. Photographs take that treatment invisibly. Flat colour, text and sharp edges do not — they are where the block boundaries and coloured fringing show up, so keep the quality high if the image contains any.

There is no transparency to preserve — BMP files do not carry an alpha channel, so every pixel is opaque to begin with. Converting to a format that supports transparency does not create any; it only means you could add it later in an editor.

Expect the file size to collapse. BMP stores three bytes per pixel with no compression at all, so a 12-megapixel image sits around 36 MB before anything is done to it. Re-encoding as JPG routinely produces a file a fiftieth of that size with nothing visible lost, because there was never any compression to preserve.

Frequently asked questions

Is this BMP to JPG converter really free and private?

Yes. Conversion happens entirely in your browser using the Canvas API — your BMP bitmaps are never uploaded to a server, there is no file limit, no watermark and no sign-up.

Can I convert multiple BMP files at once?

Yes — drop any number of files and they convert in one batch. Use "Download all" to save the results as a single ZIP.

Does converting BMP to JPG lose quality?

This is where the file size actually drops. A BMP stores its image without discarding anything; JPEG works in 8×8 blocks and throws away the fine detail inside each one, then usually halves the colour resolution as well through chroma subsampling. Photographs take that treatment invisibly. Flat colour, text and sharp edges do not — they are where the block boundaries and coloured fringing show up, so keep the quality high if the image contains any.

What quality setting should I use for the JPG?

Around 80% suits almost everything. Below about 60% the block artifacts become visible on flat areas and around hard edges; above 90% the file grows quickly for a difference nobody sees. If the image contains text or a logo, err higher — lossy compression treats sharp edges worst.

Will I lose anything by leaving BMP behind?

Effectively nothing. BMP stores raw pixels with no compression and, in its common variants, no transparency — so there is no quality advantage to preserve. The conversion is close to pure size saving.

Related conversions

PNG → JPGWebP → JPGHEIC → JPGAVIF → JPGGIF → JPGBMP → PNG

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