Lossless baseline for further work.
ICO preserves every detail of the source JPEG, which prevents additional quality loss during subsequent edits or re-encoding. The original JPEG compression cannot be undone, but no new artifacts will be introduced.
WHY CONVERT
01
ICO preserves every detail of the source JPEG, which prevents additional quality loss during subsequent edits or re-encoding. The original JPEG compression cannot be undone, but no new artifacts will be introduced.
02
ICO is accepted by a wider range of image viewers, editors, and content systems than JPEG. The conversion removes a recurring compatibility friction without changing what the file actually contains.
03
ICO is well documented and decodable by long-lived tooling, which matters for archives, deliverables, and any file that needs to outlive the software that created it.
Visit this page on any modern browser — no install, no signup, no plugin.
Drag your JPEG into the drop area, or click to pick one from your device.
Conversion runs entirely in your browser. When it's done, your ICO file downloads to your device.
QUALITY & FIDELITY
FORMAT SPECS
| JPEG | ICO | |
|---|---|---|
| Extensions | .jpeg .jpg | .ico |
| MIME types | image/jpeg | image/vnd.microsoft.icon image/x-icon |
| Introduced | 1992 | 1985 |
| Maintainer | JPEG Group / ISO | Microsoft |
| Magic # | FF D8 FF | 00 00 01 00 |
| Spec | View spec ↗ | View spec ↗ |
COMPATIBILITY
| Platform | Windows | macOS | iOS | Android | Chrome | Firefox | Safari | Edge |
|---|---|---|---|---|---|---|---|---|
| JPEG | Native | Native | Native | Native | Native | Native | Native | Native |
| ICO | Native | App | App | App | Native | Native | Native | Native |
Why LocalConvert
| Category | LocalConvert | Cloud converters |
|---|---|---|
| PRIVACY | Files never leave your device. The whole pipeline runs in your browser via WebAssembly. | Files travel to a remote server, sit in queue storage, and may be retained for analytics or moderation. |
| COST | Free, no signup, no daily quotas. | Often free for small files; paid tiers for batch / large / commercial use. |
| LIMITS | Limited only by your device's memory and CPU. Multi-GB files OK on desktop. | Typical 100 MB to 1 GB per-file caps, plus rate limits. |
A lossy format for photographic images that strikes a strong balance between size and quality.
Typical uses
Photos, web images, email attachments.
A container that can hold multiple sizes and bit depths of an icon image. Used for application icons and browser favicons.
Typical uses
Favicons, Windows app icons.
Yes. LocalConvert is completely free, with no signup and no per-file or per-day limits.
No. JPEG to ICO conversion happens entirely inside your browser using WebAssembly — your file never leaves your device.
There's no fixed cap — the practical limit is your device's available memory. Very large files may take longer or fail on low-RAM devices.
Yes — once the page has loaded, JPEG to ICO conversion works without an internet connection. Re-open the page once to cache it.
LocalConvert uses the industry-standard tools (FFmpeg, ImageMagick, Pandoc) — quality matches what professionals use on the command line. Lossy formats will still lose some quality on each re-encode.
Last verified:
JPEG to ICO is processed in your browser with WebAssembly. No upload, no tracking, no limits. Your file never leaves your device.