Convert ICO to BMP Online — Free & Private
Converting ICO to BMP re-encodes an image from Windows Icon into Bitmap Image File / Device Independent Bitmap. This free converter does it entirely inside your browser — your files are never uploaded — and handles unlimited batches with no sign-up, no watermark and no software to install.
Drag & drop your ICO files here
Batch conversion supported · up to 50 MB per file
🔒 Processed locally in your browser — nothing is uploaded.
How to convert ICO to BMP
To convert ICO to BMP: add your files to the converter above, confirm BMP is selected as the output format, press Convert, then download the result. The whole process runs in your browser and takes a few seconds.
- Add your files. Drag ICO files onto the box above, or click Choose files to browse. Multiple files at once are fine — there is no limit on how many.
- Check the settings. BMP is already selected. Quality is fixed because this target is lossless. Turn on Resize output if you need specific dimensions.
- Press Convert. Each file is decoded, redrawn and re-encoded on your device, with progress shown per file.
- Download. Take files individually, or use Download all as ZIP for the whole batch.
Why convert ICO to BMP?
Converting ICO to BMP usually comes down to compatibility or file size. Legacy Windows software and embedded systems that need raw pixel data with no decoding step.
ICO vs BMP: what actually changes?
The practical differences are compression, transparency and compatibility. ICO is container with supported at 32-bit colour depth transparency; BMP is uncompressed with only in the rarely supported 32-bit variant transparency. The table below sets out every difference that affects the result.
| Property | ICO | BMP |
|---|---|---|
| Compression | Container | Uncompressed |
| Transparency | Supported at 32-bit colour depth | Only in the rarely supported 32-bit variant |
| Animation | Not supported — the .ani format handles that | Not supported |
| Colour depth | Up to 32-bit, including an alpha channel | 1, 4, 8, 16, 24 or 32-bit |
| Introduced | 1985 | 1990 |
| Browser support | Universal for favicons; the original favicon format | Supported for display, but effectively never used on the web |
| Typical size | Depends entirely on how many sizes are included | Frequently 20–50× a JPG of the same image |
| Best for | Website favicons and Windows application icons, where several sizes must live in one file. | Legacy Windows software and embedded systems that need raw pixel data with no decoding step. |
What is a ICO file?
ICO stands for Windows Icon. Introduced in 1985 by Microsoft, it uses container compression and is best suited to website favicons and Windows application icons, where several sizes must live in one file.
The Windows and favicon format. Holds several square sizes in one file; 16×16, 32×32 and 48×48 are the sizes browsers actually reach for.
| Property | ICO |
|---|---|
| Full name | Windows Icon |
| File extensions | .ico |
| MIME type | image/x-icon |
| Introduced | 1985 |
| Developed by | Microsoft |
| Compression | Container |
| Colour depth | Up to 32-bit, including an alpha channel |
| Transparency | Supported at 32-bit colour depth |
| Animation | Not supported — the .ani format handles that |
| Browser support | Universal for favicons; the original favicon format |
| Typical file size | Depends entirely on how many sizes are included |
ICO strengths
- Stores multiple resolutions in a single file
- The most broadly compatible favicon format, including very old browsers
- Alpha transparency for non-square icon shapes
ICO limitations
- Restricted to icon-sized square images
- No use outside icons
- Larger than a single equivalent PNG, since it holds several copies
What is a BMP file?
BMP stands for Bitmap Image File / Device Independent Bitmap. Introduced in 1990 by Microsoft, it uses uncompressed compression and is best suited to legacy Windows software and embedded systems that need raw pixel data with no decoding step.
An uncompressed Windows bitmap. Enormous files, but dead simple — still used by some legacy Windows and embedded software.
| Property | BMP |
|---|---|
| Full name | Bitmap Image File / Device Independent Bitmap |
| File extensions | .bmp, .dib |
| MIME type | image/bmp |
| Introduced | 1990 |
| Developed by | Microsoft |
| Compression | Uncompressed |
| Colour depth | 1, 4, 8, 16, 24 or 32-bit |
| Transparency | Only in the rarely supported 32-bit variant |
| Animation | Not supported |
| Browser support | Supported for display, but effectively never used on the web |
| Typical file size | Frequently 20–50× a JPG of the same image |
BMP strengths
- Dead simple structure — trivial for any program to read
- No compression means no compression artefacts at all
- Long-standing support across Windows tooling
BMP limitations
- Enormous files — width × height × 3 bytes, with no compression
- Transparency support is inconsistent in practice
- Nobody uses it on the web, for good reason
Does converting ICO to BMP lose quality?
No. BMP is lossless, so the conversion writes every decoded pixel exactly as it is. Note that any quality already lost inside the original ICO file cannot be recovered — lossless means nothing further is lost, not that damage is undone.
Two distinct things are often confused here. The first is whether the target format discards data: BMP is uncompressed, so it does not. The second is whether the source already lost data: ICO is container, so the source holds the original detail intact.
A practical rule: converting repeatedly between lossy formats compounds the damage each time. If you expect to edit an image more than once, work in a lossless format and export to a lossy one only at the end.
Is it safe to convert ICO files here?
Yes, and you can verify it rather than trust it. Your ICO file is read, decoded and re-encoded inside your browser tab. There is no upload endpoint on our side, so no copy of your image exists anywhere but your own device.
Most online converters upload your file to a server, process it there and promise to delete it later. That promise is unverifiable, and it does not survive a breach, a misconfigured storage bucket or a legal request. This tool removes the question entirely: the code comes to you, the file stays put.
To confirm it for yourself, open your browser’s developer tools, switch to the Network tab, and convert a file. You will see the page assets load and nothing carrying your image leave. It also works with your connection switched off entirely, once the page has loaded.
ICO and BMP at a glance
ICO files use the image/x-icon MIME type and the .ico extension; BMP files use image/bmp and .bmp. The summary below covers the properties that matter when choosing between them.
| ICO | BMP | |
|---|---|---|
| Full name | Windows Icon | Bitmap Image File / Device Independent Bitmap |
| Extension | .ico | .bmp, .dib |
| MIME type | image/x-icon | image/bmp |
| Year | 1985 | 1990 |
| Best for | Website favicons and Windows application icons, where several sizes must live in one file. | Legacy Windows software and embedded systems that need raw pixel data with no decoding step. |
ICO to BMP: frequently asked questions
- How do I convert ICO to BMP?
- Open this page, drag your ICO files onto the drop zone, and press Convert. BMP is already selected as the output format. The conversion runs in your browser and finishes in seconds, then you download the result individually or as a ZIP.
- Is this ICO to BMP converter free?
- Yes, completely. There is no account, no daily limit, no watermark and no paid tier. You can convert as many ICO files as you like, as often as you like.
- Are my ICO files uploaded to a server?
- No. The conversion runs entirely in your browser using the Canvas API and WebAssembly codecs. Nothing about your file is transmitted to us, so there is nothing for us to store, share or lose. You can verify this by opening your browser's Network tab while converting.
- Will converting ICO to BMP reduce quality?
- BMP is lossless, so every pixel that survives decoding is written exactly as it is. No further quality is lost in the conversion itself.
- Will the file get bigger or smaller?
- BMP files are typically frequently 20–50× a jpg of the same image, against depends entirely on how many sizes are included for ICO. The converter shows the before and after size for every file so you can see the exact result.
- Can I convert multiple ICO files at once?
- Yes. Drop the whole batch in and they convert one after another with individual progress. Download them one by one, or take the entire set as a single ZIP file built in your browser.
- Does BMP support transparency?
- Yes — only in the rarely supported 32-bit variant. Transparent areas in your ICO file are preserved in the BMP output.
- Is there a file size limit?
- Each file is capped at 50 MB, because conversion happens in your browser's memory and very large files can crash a tab, particularly on phones. There is no limit on how many files you convert.
- Does it work on iPhone, Android, Mac and Windows?
- Yes. It runs in any modern browser on any operating system — there is nothing to install. Supported for display, but effectively never used on the web.
- Do I need to install software or sign up?
- Neither. There is no download, no extension, no account and no email address required. Open the page and convert.
Related conversions
Need to go the other way? Try BMP to ICO. Other conversions involving these formats: