画像 → ICO 変換ツールとは？

無料のオンライン画像→ICO 変換ツール。PNG、JPG などの画像を Windows ICO アイコンに変換。

A favicon is the small icon displayed in browser tabs, bookmarks, and address bars. It is a tiny but essential element of website identity — users recognize your site by its favicon among dozens of open tabs. Image to ICO Converter creates a properly formatted .ico file from any image, generating all required sizes in a single file.

The ICO format is unique because it packages multiple image sizes in one file. When a browser or operating system requests a favicon, it selects the best size for the display context. This converter generates 6 resolutions: 16x16 (browser tab), 24x24 (taskbar), 32x32 (favorites), 48x48 (desktop shortcut), 64x64 (high-DPI displays), and 128x128 (retina displays). All sizes are embedded in a single .ico output file.

Upload a PNG, JPG, WebP, GIF, or SVG image. For best results, use a PNG with transparency — the icon will display properly on any background color. The preview shows each generated size so you can verify quality before downloading. Small details that look good at 128px may become indistinct at 16px, so the preview helps you decide if a simpler design is needed.

All processing happens locally in your browser. No images are uploaded to any server. This is critical for design work where logo files are proprietary and should not leave your device.