ICO to BMP Converter: Free, Private, No Upload
Convert ICO files to BMP in your browser. Lossless output, batch up to 20 files at once, no upload, no account, no watermark. Your files never leave your device.
- ICO to BMP
- Batch up to 20 files
- No upload, no account
- Metadata stripped
- 1Add up to 20 images
- 2Pick from 18 formats
- 3Download or copy the code
Processed on your device. Your images are never uploaded, and metadata is stripped. How we keep it private
How do I convert ICO to BMP for free?
Drop your ICO files into the tool above, choose BMP as output, and download the result. Everything runs in your browser, so nothing is uploaded and there is no limit or watermark. It works on Windows, Mac, Linux, ChromeOS, iOS and Android — anywhere you have a modern browser.
- Price
- Free, no credits and no daily cap
- Account required
- No
- File uploaded to server
- No, processed locally in your browser
- Batch limit
- Up to 20 files at once
- Input format
- ICO
- Output format
- BMP
- Best for
- BMP workflows, lossless quality, editing, printing
- Works on
- Chrome, Edge, Firefox, Safari, iOS and Android browsers
- Privacy
- No upload, no tracking, metadata stripped
- Output quality
- Lossless, exact pixels
How to convert ICO to BMP
- 1
Drop your ICO files
Drag up to 20 ICO files onto the page or click to choose them. Everything runs in your browser.
- 2
BMP is preselected
Output is already set to BMP. Adjust quality, resize or batch if you want.
- 3
Download
Save each BMP, or download all of them together as a ZIP.
ICO to BMP: what changes and when it makes sense
ICO is an Windows icon format. It is best known for packing several sizes (16, 32, 48, 256 pixels) into a single file. The main drawbacks are a maximum size of 256 by 256 pixels and little use outside icons.
BMP is a Bitmap image format. It is best known for a simple structure that legacy programs and embedded systems can read without a decoder library. The main drawbacks are enormous files and no reliable transparency.
ICO vs BMP at a glance
| Property | ICO | BMP |
|---|---|---|
| Type | Container format | Raster image |
| Compression | A container holding one or more bitmaps, each stored as BMP or PNG data | Usually uncompressed (run-length encoding exists but is rare) |
| Transparency | Full alpha channel with soft edges | None |
| Animation | No | No |
| Colour depth | Up to 32-bit colour with an 8-bit alpha channel | 1 to 32 bits per pixel |
| Support | Supported by Windows and by browsers as a favicon, but most image viewers and editors do not open it directly | Opens in browsers and most desktop software, but almost never used on the web |
| History | Introduced by Microsoft with Windows 1.0 in 1985. The modern 32-bit alpha version became standard with Windows XP (2001). Windows Vista (2007) added PNG compression inside ICO for icons larger than 48x48. | Created by Microsoft for Windows 1.0 in 1985 as the native bitmap format for the Windows Graphics Device Interface. The "BM" signature has been unchanged since then. Still used in embedded systems and legacy Windows software. |
What actually changes in this conversion
- Both ICO and BMP are lossless, so the pixels come through unchanged.
- BMP cannot store transparency, so transparent areas are filled with white.
- EXIF, GPS and camera data are stripped on every conversion. That is good for privacy, but you lose capture dates.
About ICO: history and technical details
Introduced by Microsoft with Windows 1.0 in 1985. The modern 32-bit alpha version became standard with Windows XP (2001). Windows Vista (2007) added PNG compression inside ICO for icons larger than 48x48.
Technical: Container holds 1-65535 images. Each entry has a 16-byte directory: width, height, colour count, planes, bit count, data size, data offset. Images are BMP (DIB) or PNG. Max dimension 256x256. Typical Windows icons use 16, 32, 48, 64, 128, 256.
Real-world size: A 6-size favicon.ico is typically 15-40 KB. A single 256x256 PNG favicon is 8-15 KB. Modern best practice uses separate files for 16, 32, 180 (Apple), 192, 512 (PWA).
Popular tools: IcoFX, GIMP, Adobe Photoshop (with plugin), ImageMagick, Favicon Generator, RealFaviconGenerator.
Alternatives: PNG (single size, widely accepted), SVG (sharp at any size), favicon.ico (still needed for legacy).
About BMP: what you get
Created by Microsoft for Windows 1.0 in 1985 as the native bitmap format for the Windows Graphics Device Interface. The "BM" signature has been unchanged since then. Still used in embedded systems and legacy Windows software.
Technical: File header 14 bytes (signature, size, reserved, offset) followed by DIB header (40+ bytes). Supports 1, 4, 8, 16, 24, 32-bit pixels. Rows padded to 4-byte boundaries. Pixels can be stored bottom-up or top-down. Optional RLE4/RLE8 rarely used.
Real-world size: A 12-megapixel photo is 36 MB as 24-bit BMP. As JPG it is 2-4 MB (90% smaller). A 1920x1080 screen at 32-bit BMP is 8.3 MB; as PNG 200-600 KB.
Popular tools: Windows Paint, IrfanView, XnView, ImageMagick, GIMP, Adobe Photoshop, embedded dev tools.
Alternatives: PNG (lossless, 5-20x smaller), TGA (game pipelines), TIFF (professional print), JPG (lossy, much smaller).
Browser and software compatibility
ICO: Supported by Windows and by browsers as a favicon, but most image viewers and editors do not open it directly. BMP: Opens in browsers and most desktop software, but almost never used on the web.
BMP output opens in browsers and most desktop software, but very few web workflows expect it.
Why people move away from ICO
- ICO is capped at 256 by 256 pixels, so it is of no use as a general-purpose image format.
- Many image viewers and design tools cannot open ICO directly, so you need a PNG to edit it.
Why people choose BMP
- Some legacy Windows software, embedded displays and industrial tools only read BMP.
- With no compression there is no decoding step and no compression artefacts.
Common mistakes with ICO
- Creating a favicon.ico with a single 16x16 size — looks blurry on Retina
- Using ICO for general images — 256x256 limit makes it useless
- Forgetting the .ico fallback — some old browsers still request it automatically
Best practices for keeping quality
- ICO files are tiny, often 32 by 32 pixels. Scaling them up blurs, so start from a larger original when possible.
- Expect a very large file. Check the upload limit and free disk space before saving.
- Flatten any transparency first. BMP does not reliably carry an alpha channel.
- Resize before converting if the image will be shown small. A 4000 pixel photo displayed at 800 pixels wastes bytes in any format.
- Check the result at 100 percent zoom, especially around text, edges and gradients, before you replace any originals.
- Keep your original files. Conversions to a lossy format cannot be undone.
- When you convert a set of images, use the same quality setting for the whole batch. The converter handles up to 20 files at once.
ICO to BMP questions
Quick answers about privacy, quality, supported formats, file limits and how BMP works.
Why convert ICO to BMP?
BMP is lossless. It keeps every pixel exactly. It is the safe choice when you plan to edit, print or need exact pixel data.
Will converting ICO to BMP lose quality?
No. BMP is lossless, so nothing is thrown away.
Does BMP keep transparency?
No. BMP does not support transparency. Transparent areas will be filled with white.
Are my files uploaded?
Never. Everything runs in your browser. Your files never leave your device. Open DevTools Network tab while processing — you will see no upload request.
Can I convert many files at once?
Yes, up to 20 files at once. Download them individually or all together as a ZIP.
Does the converter strip metadata?
Yes. Browsers do not pass EXIF data through a canvas, so GPS, camera model and dates are removed on every conversion. That is good for privacy.
Is it free?
Yes. No credits, no daily cap, no account, no watermark. The practical limit is your device memory.
Why is BMP so large?
Because it stores raw pixel data with little or no compression. A 12-MP photo as 24-bit BMP is 36 MB, compared to 2-4 MB as JPG. The tradeoff is speed (no decoding needed) and lossless quality.
Your files never leave your device
No upload, no account, no tracking. Everything happens in your browser using the Canvas API and WebAssembly. You can confirm this in your browser's DevTools Network tab while the tool runs — no request carries your file. See why ToolDeck is different.