Question 1

What size and resolution should I use for a high‑quality ICO file?

Accepted Answer

For a high‑quality ICO that scales well across Windows, include multiple square sizes in one file. The most common set is 16×16, 32×32, 48×48, 64×64, 128×128, and 256×256. This ensures crisp display in taskbars, explorers, shortcuts, and high‑DPI contexts.
Use a color depth of 24‑bit or 32‑bit (with 8‑bit alpha for transparency). For the largest size, prefer 256×256 PNG‑compressed inside the ICO container, which is supported by modern Windows and keeps quality high with smaller file size.
Design at the largest resolution first (e.g., 1024×1024 or 512×512) and export clean, pixel‑hinted downsizes to the target icon set. Keep artwork centered, avoid thin lines at 1‑px scales, and verify each embedded size for legibility and edge crispness.

Question 2

Can I create a multi‑resolution ICO (16x16, 32x32, 48x48, 256x256) from a single JPG?

Accepted Answer

Yes—you can generate a multi‑resolution ICO (16×16, 32×32, 48×48, 256×256) from a single JPG by resizing the source image to each target dimension and packaging them into one .ico file; for best results, start from the highest possible resolution, convert it to PNG first if you need transparency, then create the 16, 32, 48, and 256 versions with proper sharpening, and export them together using an icon editor or an online converter that supports multi-size ICO output.

Question 3

Will transparency be preserved when converting a JPG to ICO?

Accepted Answer

No. A JPG does not support transparency, so if you convert a JPG to ICO, the resulting icon will not magically gain a transparent background. The background will remain solid (usually white or whatever color was in the JPG).
To get a transparent ICO, start with an image format that supports alpha (e.g., PNG), then convert that to ICO. During conversion, ensure you preserve the alpha channel and choose appropriate icon sizes.

Question 4

Which color depth is recommended for icons (8‑bit, 24‑bit, 32‑bit with alpha)?

Accepted Answer

Use 32‑bit with alpha for modern icons to get full 24‑bit color plus an 8‑bit transparency channel for smooth edges and overlays; choose 24‑bit only if you don’t need transparency, and reserve 8‑bit (256 colors) for legacy or size‑critical cases where bandwidth or memory is extremely limited.

Question 5

What is the maximum file size or dimensions supported for JPG to ICO conversion?

Accepted Answer

The maximum file size supported for JPG to ICO conversion typically ranges up to 20–50 MB, depending on the tool. Larger files may fail to upload or process due to memory limits. For best performance, keep your JPG under 15 MB when possible.
For dimensions, most converters accept large JPGs, but ICO outputs are limited to standard icon sizes: 16×16, 32×32, 48×48, 64×64, 128×128, 256×256, and sometimes up to 512×512. The input can be bigger, but it will be downscaled to these sizes.
To ensure the best result, provide a square image (1:1 aspect ratio) and aim for at least 256×256 pixels. If your JPG is very large, consider resizing or compressing it before conversion to avoid errors and speed up processing.

Question 6

Are there any limitations with rounded corners or complex gradients in the final icon?

Accepted Answer

Yes—most modern icon formats support rounded corners and complex gradients, but results can vary by output format and platform rendering: vector-based outputs (like SVG) preserve smooth curves and gradient transitions best, while raster formats (like PNG, JPG) may show banding or aliasing at small sizes; to minimize issues, use sufficiently high resolution, enable anti-aliasing, avoid extremely subtle gradient steps, and test dark/light backgrounds and different icon sizes to ensure consistent appearance.

Question 7

What’s the difference between a JPG file and an ICO file?

Accepted Answer

A JPG is a widely used photo format that uses lossy compression to reduce file size, making it ideal for photographs and web images. It supports millions of colors but does not support transparency or multiple sizes in one file. JPGs are best for rich, detailed images where small file size matters more than pixel-perfect edges.
An ICO is a Windows icon format that can store multiple square images at different sizes and color depths in a single file, often including transparency. It’s designed for app and website favicons, ensuring crisp display across various resolutions. Unlike JPG, ICO prioritizes sharp edges and transparency over photographic compression.

Question 8

How can I ensure the ICO works correctly on Windows, macOS, and web favicons?

Accepted Answer

Use a properly built ICO that contains multiple sizes and color depths to cover Windows, macOS, and web contexts. Include at least 16×16, 32×32, and 48×48 (plus 64×64 or 256×256 for high DPI), all with PNG-compressed entries for best quality and transparency. Verify the icon is not oversized in bytes, keeps a square aspect ratio, and uses sRGB color. Test in Windows Explorer/Taskbar and macOS Finder/Quick Look to confirm the OS picks the right embedded size.
For websites, serve a dedicated favicon.ico at the site root and reference modern sizes explicitly. In your HTML head, add <link rel=

Convert JPG to ICO Online & Free

More online JPG converters to transform your images

Frequently Asked Questions about JPG to ICO Conversion