How to convert HEIC to BMP without uploading it
Every "free" online HEIC converter you've used uploads your photos to a company server, converts them there, and — in several documented cases — keeps a copy or a live download link for days. For personal photos and anything you wouldn't post publicly, that's an unnecessary risk. The safer approach is to convert the file where it already is: on your own device.
This tool does exactly that. When you drop a HEIC here, your browser:
- Decodes the HEIC locally — a vendored HEVC decoder runs in a Web Worker, so the page stays responsive while it works. The decoder loads once, on your first convert, and never again for the rest of the visit.
- Reads the photo's EXIF orientation data and stores the output upright, so a portrait phone photo doesn't come back sideways. The rest of the EXIF data, including location, is dropped.
- Re-encodes the pixels as a raw BMP with a pure-JavaScript BMP encoder — BITMAPINFOHEADER, bottom-up rows, at the bit depth you chose. Your original file is never modified.
What makes this converter different
The converters that top the results for this search mostly upload your files to a server (XConvert and HexaConverter both convert server-side, and HexaConverter caps free batches at three files), and the client-side ones we found cap the bit depth — several offer only 24-bit output, one offers only 24-bit and 32-bit, and one rejects multi-still sequences outright. This page is the only dedicated HEIC-to-BMP page we found that combines a batch of 20 files with a ZIP download, the full bit-depth range (1/8/16/24/32-bit), Floyd–Steinberg dithering, hardware and retro destination presets, a background colour for transparency, and a live network-request counter so you can verify the privacy claim yourself. It runs entirely in your browser — there is no server to upload to.
When is BMP the right choice for a HEIC?
Almost never for sharing or storage — HEIC is smaller and PNG is lossless and smaller still. BMP earns its place when the destination demands raw pixels: legacy Windows software and GDI tooling, printer utilities, embedded firmware and machine-vision rigs that read uncompressed data, and sprite or retro-game editors that load 1-bit or 8-bit BMPs. If the program you are feeding accepts anything else, use HEIC to PNG instead and keep the smaller file.
Honest limitations
No quality recovery
HEIC throws away detail when it compresses. Converting cannot restore detail: a BMP holds the same decoded pixels, uncompressed — it cannot put back what HEIC discarded. Blocky artefacts in the HEIC stay blocky in the BMP.
BMPs are much larger than HEICs
Expect roughly 12× the size for a 24-bit BMP of a photo, and more at 32-bit. Every file shows its size multiple honestly, and the batch bar shows the total before you download anything.
10-bit colour folds to 8-bit
iPhones can save 10-bit HEIC files, but the decode path in the browser produces 8-bit colour. The extra two bits of depth are lost — the BMP holds at most 8 bits per channel, at any bit depth.
16-bit loses colour depth
16-bit BMP keeps 5 bits per channel — 32,768 colours instead of 16.7 million. Smooth gradients will band. Use it only when the destination insists on 16-bit.
8-bit and 1-bit are approximations
8-bit output is a 256-colour palette built by median cut; 1-bit is black and white only. Dithering fakes the missing shades by speckling pixels, but detail and smooth colour are lost either way.
Transparency is flattened
BMP has no useful transparency. Transparent pixels are flattened onto the background colour you pick, and 32-bit BMPs write alpha 255 for every pixel. Most readers ignore BMP alpha entirely.
Metadata is stripped
Camera metadata (EXIF, including location) is dropped on re-encode. The orientation tag is read and applied first, so the output is stored upright. A Live Photo or burst converts its first still only — BMP cannot hold the extra frames.