Why can't this tool convert HEIC to BMP directly in the browser?

HEIC files use the HEVC (H.265) video codec for compression. Web browsers do not have access to the system HEVC decoder, so JavaScript cannot read the raw pixel data needed to re-encode it as BMP. Conversion must happen at the OS level or in a native desktop application that can call the system codec.

What is BMP format and why would I use it?

BMP (Bitmap) is an uncompressed raster image format developed by Microsoft. It stores raw pixel data with no lossy compression, making it useful for applications that need pixel-perfect accuracy, legacy software compatibility, or industrial/embedded systems. The trade-off is large file sizes — a 12 MP photo can exceed 36 MB as BMP.

Is HEIC to BMP conversion lossy?

HEIC uses lossy HEVC compression, so some quality was already discarded when the iPhone saved the photo. Converting to BMP does not add further compression, so the BMP output faithfully represents the decoded pixel data from the HEIC file — no additional quality loss occurs during the conversion step itself.

How do I convert HEIC to BMP on Windows without installing software?

Use one of the online converters listed in this guide (Convertio, CloudConvert, or HEICtoJPEG.app). Upload your HEIC file, choose BMP as the output format, and download the result. For regular or batch conversions, installing the free HEIF Image Extensions from the Microsoft Store plus Microsoft Paint is easier.

Can I convert multiple HEIC files to BMP at once?

Yes, but Finder’s built-in Convert Image Quick Action does not offer BMP output. Use a batch-capable converter such as XnConvert, or export individual files through Preview on macOS. Check the output settings before processing a large batch.

Does converting HEIC to BMP increase the file size?

Significantly — BMP is uncompressed. A typical 3 MB iPhone HEIC photo can become 30–50 MB as BMP, depending on resolution and color depth. If file size is a concern, consider converting to PNG (lossless compression) or JPEG (smaller, lossy) instead of BMP.

HEIC to BMP Converter

Learn how to convert HEIC/HEIF photos to BMP on macOS, Windows, or online — with a format comparison table and recommended tools.

Why no in-browser conversion?

HEIC files use the HEVC (H.265) codec — a codec that web browsers cannot access. Converting HEIC requires your operating system's native decoder. Use the methods below to convert your files on macOS, Windows, or via a trusted online service.

Convert HEIC to BMP on macOS

Method A — Preview App

1 Open the .heic file in Preview.
2 Choose File › Export.
3 Hold the Option key while opening the Format menu to reveal additional formats.
4 Choose Microsoft BMP, select a destination, and click Save.

Method B — XnConvert for batch conversion

1 Install XnConvert from its official site or the Mac App Store.
2 Add the HEIC files in the Input tab.
3 In Output, choose BMP and select a destination folder.
4 Review the output options, then click Convert.

Tip: For batch conversion of many files, use Automator or the free XnConvert app — both fully support BMP output on macOS.

Convert HEIC to BMP on Windows

Step 1 — Install the HEIF Image Extensions (free, one-time)

1 Open the Microsoft Store (search for it in the Start menu).
2 Search for HEIF Image Extensions and install the free Microsoft extension.
3 Optionally also install HEVC Video Extensions ($0.99) for full HEIC support — the free extension covers most iPhone photos.
4 Restart any open image application after installation.

Step 2 — Convert with Microsoft Paint

1 Right-click the .heic file and choose Open with › Paint.
2 In Paint, click File › Save as › BMP picture.
3 Choose a destination folder, confirm the filename, and click Save.

Recommended free tool for batch conversion: iMazing HEIC Converter — drag and drop multiple HEIC files, choose BMP (or JPEG/PNG), and convert in seconds. No account required.

HEIC vs BMP — Format Comparison

Property	HEIC / HEIF	BMP (Bitmap)
Full name	High Efficiency Image Container	Bitmap Image File
Compression	Lossy (HEVC / H.265)	None (uncompressed)
Typical file size	3–5 MB per 12 MP photo	30–50 MB per 12 MP photo
Quality	Excellent at small sizes	Pixel-perfect (no further loss)
Color depth	Up to 16-bit per channel (HDR)	Up to 32-bit ARGB
Browser support	Limited (requires OS codec)	Limited (not a web format)
OS support	macOS 10.13+, iOS 11+, Windows 10+ with extensions	Universal (all platforms)
Typical use	iPhone photos, camera storage	Legacy apps, print, archival
Transparency	Yes (HEIF supports alpha)	Yes (32-bit ARGB)
Animation	Yes (HEIF image sequence)	No
Open standard	Yes (ISO 23008-12)	Yes (Microsoft / open spec)

Should You Convert to BMP?

Use BMP when

A legacy application specifically requires BMP input
You need pixel-exact uncompressed data for processing
An industrial or embedded system expects raw bitmap
Print workflows require uncompressed source files

Use PNG instead when

You want lossless quality with much smaller file sizes
You need transparency (alpha channel)
The destination supports PNG (nearly universal)
You are archiving screenshots or graphics

Use JPEG instead when

Sharing photos via email or social media
Uploading to websites that do not support HEIC
Storage space or bandwidth is a concern
Compatibility with the widest range of apps is needed

Summary

HEIC (High Efficiency Image Container) is the default photo format on iPhones since iOS 11. While it produces smaller files than JPEG, it is not supported by many applications — including those that require uncompressed BMP (Bitmap) files for printing, archiving, or compatibility. Because HEIC uses a proprietary codec not available in web browsers, conversion must happen on your operating system or via a trusted online service. This guide walks you through every conversion method step by step.

How it works

HEIC files store images using the HEIF container and HEVC (H.265) codec — a codec browsers cannot decode without native OS support.
To convert to BMP, your OS or a desktop application must first decode the HEIC file using the system codec.
The decoded pixel data is then re-encoded into the uncompressed BMP format.
On macOS, the built-in Preview app handles this natively — no extra software needed.
On Windows 10/11, install the free HEIF Image Extensions from the Microsoft Store to unlock HEIC support.
Alternatively, use a trusted online converter (listed below) if you cannot install software.

Use cases

Convert iPhone HEIC photos to BMP for use in legacy Windows software.
Prepare HEIC images for printing workflows that require uncompressed bitmap files.
Archive iPhone photos in an uncompressed format for long-term storage.
Convert HEIC files to BMP for compatibility with graphics editors that do not support HEIC.
Supply BMP images to industrial or embedded systems that require raw pixel data.
Batch-convert a folder of iPhone photos to BMP on macOS or Windows.

Frequently Asked Questions

Last updated: 2026-06-11 · Reviewed by Nham Vu