TGA to ICO Crop: Complete Conversion Guide for Favicons & Icons
🚀 Ready to crop and convert? TGA to ICO Crop Converter — free, browser-based, no sign-up.
Open Tool →What Is ICO and Why Does It Matter for Favicons?
ICO is the native Windows icon and favicon format, originally developed by Microsoft for use in Windows program icons and later adopted as the universal favicon standard by every web browser. The ICO container is unusual among image formats in that it can hold multiple differently-sized images in a single file — a browser or operating system picks the most appropriate size for the context automatically. A single well-formed ICO file can serve as a browser tab favicon, a desktop shortcut icon, a taskbar icon, and a Windows shell icon without any additional configuration.
Modern ICO files use the PNG-in-ICO encoding introduced with Windows Vista: each size tier inside the container is a standard PNG file, supporting full 32-bit alpha-channel transparency and lossless quality. This is a significant improvement over the older BMP-based ICO encoding, which was limited to 8-bit palettes and binary transparency.
What Is TGA and When Does It Produce Icon-Worthy Assets?
TGA (Truevision TGA) is the long-standing raster format of game development and 3D production pipelines. Game logos, application icons, UI elements, and sprite assets are routinely stored as TGA files during production — and converting a cropped region of one of those assets into an ICO is a natural step when deploying the game or application to the web or Windows desktop. Rather than recreating the icon in a separate design tool, you can extract exactly the right region from the production TGA and convert it directly to ICO in a single browser operation.
Why Crop Before Converting to ICO?
TGA source files used in production are often large textures or sprite sheets containing many elements. Cropping lets you isolate the specific icon element — a logo, a character portrait, a UI button — before converting. This is more precise than converting the entire TGA and hoping the icon rendering context crops it correctly. It also avoids including surrounding content that was not intended to be part of the icon. The crop tool preserves the source TGA untouched, extracting only the pixels you specify.
Understanding Multi-Size ICO Output
The TGA to ICO Crop Converter generates up to four size tiers in a single ICO file: 256×256, 128×128, 64×64, and 32×32 pixels. Each tier is independently encoded as a 32-bit PNG-in-ICO, derived from the full-resolution crop. Size tiers larger than your crop's actual dimensions are skipped — if you crop a 48×48 pixel region, only the 32×32 tier is generated.
Why multiple sizes? Browsers and operating systems request different icon sizes in different contexts. Windows displays a 32×32 icon in Explorer file listings, a 64×64 in medium-size view, and 256×256 for large icons and thumbnails. Providing all tiers in a single ICO ensures the OS always selects a native-resolution version rather than scaling a single image — which produces sharper icons at every display size.
Transparency in ICO from TGA
One of the most practical advantages of the PNG-in-ICO format is full alpha-channel support. Game icons and UI elements stored as 32-bit TGA files often have transparent backgrounds — the actual icon shape is cut out from the transparency. The TGA to ICO Crop Converter preserves that alpha channel across all size tiers in the output ICO. The result is an icon with a proper transparent background that integrates cleanly with any browser, taskbar, or desktop shell colour or wallpaper without a white or solid bounding box.
This is a meaningful difference from older ICO workflows that required a specific background colour to be "erased" or masked manually. With PNG-in-ICO and a 32-bit TGA source, the transparency simply carries through end-to-end.
Why Crop a Square Region for Icons
ICO size tiers are always square. When the tool generates a 32×32 or 256×256 tier from a non-square crop, it scales the crop to fit the square target — which will distort the content horizontally or vertically. For the best results, drag the crop handles to define a square selection (equal width and height) before converting. Many TGA game assets — logos, character portraits, UI buttons — are already square or close to square, making this a natural fit.
When Should You Crop and Convert TGA to ICO?
- Website favicons from game assets. When launching a game's website, converting the game logo or mascot from a TGA asset directly to a multi-size favicon.ico is the most direct path from production asset to web deployment.
- Windows application icons. Executable icons (.exe, .dll) require ICO format. Converting a TGA production icon to ICO is the first step in the Windows application packaging workflow.
- Progressive web app icons. While PWAs primarily use PNG icons, providing an ICO at the root as favicon.ico is still recommended for maximum browser compatibility.
- Electron and desktop app packaging. Electron applications on Windows require an ICO file for the application window icon and taskbar icon. A TGA-to-ICO conversion produces the required file directly from the production asset.
- Shortcut and installer icons. Windows installer tools (NSIS, Inno Setup, WiX) require ICO files for setup wizard icons and desktop shortcut icons.
TGA vs ICO: Format Comparison
| Property | TGA | ICO (PNG-in-ICO) |
|---|---|---|
| Primary use | Game assets, 3D renders, textures | Favicons, Windows app icons, shortcuts |
| Multi-size container | No — single image per file | Yes — multiple sizes in one file |
| Browser favicon support | Not supported | Universal — all browsers |
| Transparency | Full alpha channel (32-bit) | Full alpha (32-bit PNG-in-ICO) |
| Max image size | Unlimited | 256×256 per tier (PNG-in-ICO) |
| OS integration | Not recognised by Windows shell | Native Windows shell format |
| Best for | Production pipelines, rendering | Icons, favicons, OS/app deployment |
How the Crop and ICO Encoding Works
The TGA to ICO Crop Converter decodes the TGA in the browser using a built-in JavaScript parser. After cropping, the tool generates each size tier by drawing the cropped region onto a separate offscreen canvas scaled to the target dimensions using drawImage. Each scaled canvas calls toBlob('image/png') to produce a PNG-encoded tier. The tiers are assembled into a valid ICO binary structure — ICONDIR header, ICONDIRENTRY records, and concatenated PNG data — entirely in a JavaScript ArrayBuffer, then downloaded as a Blob. No pixels are sent to a server at any point.
Deploying the ICO as a Favicon
After downloading the ICO from the converter, place it in your website's root directory as favicon.ico. Add the following to your HTML <head>:
<link rel="icon" href="/favicon.ico" sizes="any">The sizes="any" attribute tells browsers the ICO contains multiple sizes and to pick the best one. Browsers automatically use the highest-quality size tier available for each display context — no additional configuration is needed.
✍ Try it yourself — crop and convert a TGA to ICO in seconds.
Open TGA to ICO Crop Converter →Frequently Asked Questions
Should I crop a square region?
Yes, for best results. ICO size tiers are always square, so a non-square crop will be distorted when scaled to fit each tier's target dimensions. Drag the handles to create an equal-width-and-height selection before converting.
Does the ICO preserve alpha from my TGA?
Yes. Each tier is encoded as a 32-bit PNG-in-ICO, which supports a full alpha channel. Transparency from 32-bit TGA sources is preserved across all size tiers — no background compositing is applied.
What if my crop is smaller than 256×256?
Size tiers larger than your crop dimensions are skipped automatically. If your crop is 60×60, only the 32×32 tier is generated. For best results across all contexts, start from a source crop of at least 256×256 pixels so all four tiers can be included.
Is the conversion really free with no file size limit?
Yes. All processing runs entirely in your browser — there is no server to impose a file size limit. There are no usage caps, no watermarks, and no account required.