CUR to FITS Converter
Processing entirely on your device — large files may take a moment.
Windows Cursor and Flexible Image Transport System exist for different jobs: CUR is the Windows cursor format — structurally an ICO file with a hotspot, holding small bitmap cursor images. Convert FITS frames to PNG or JPG to preview telescope data, or pack them into a ZIP for sharing.
Because the whole conversion happens on your device, it is instant, unlimited and genuinely private — no accounts, no watermarks, no files on anyone's server. Multiple files are converted in one go.
How CUR compares to FITS
| CUR | FITS | |
|---|---|---|
| Compression | BMP/PNG members (as ICO) | None (optionally Rice/GZIP) |
| Transparency | Supported | Not supported |
| Animation | No (that is .ani) | Not supported |
| Metadata | Hotspot coordinates | Rich text header (WCS) |
| Best for | Windows cursors and UI assets | Telescope frames, science data |
How to convert CUR to FITS
- 1
Select your files
Drag & drop your CUR files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to FITS". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted FITS file individually, or grab everything at once as a ZIP archive.
About the CUR format
CUR is the Windows cursor file: structurally identical to ICO (several small bitmap sizes bundled), with the addition of a hotspot coordinate that marks which pixel is the pointer's tip. Windows ships most of its system cursors as CUR files.
Designers customizing cursors or extracting UI assets meet CUR files that no modern image tool opens. Converting to PNG (the largest embedded size) makes them editable, viewable and reusable in web apps that implement custom cursors.
+Strengths
- ✓Windows cursor standard
- ✓Multiple sizes in one file
- ✓Hotspot data travels with the image
!Limitations
- −Tiny sizes only (usually ≤48px)
- −Meaningless outside cursor use
About the FITS format
FITS (Flexible Image Transport System) has carried professional astronomy data since 1981: every file opens with a plain-text header that records telescope, instrument, exposure, filters and world coordinates, followed by raw pixel arrays — often 16-bit or float, sometimes data cubes.
Values can be negative or far above display range, so FITS never looks right in a photo viewer. Converting to PNG applies a simple scaling pass that reveals the nebula or galaxy in the numbers — good for previews, while science pipelines keep the original.
+Strengths
- ✓Self-documenting science headers
- ✓High bit depth (16/32-bit, float)
- ✓The standard of every observatory
!Limitations
- −Not display-ready
- −Files are large and uncompressed
Why convert CUR to FITS?
There is a concrete reason this conversion exists: Tiny sizes only (usually ≤48px) FITS sidesteps that — Self-documenting science headers If that is your situation, the tool above settles it in seconds, entirely on your device.
Frequently asked questions
Is this CUR to FITS converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Will I lose quality converting CUR to FITS?
No — FITS is a lossless format, so every pixel of the converted image matches your original CUR file. You can also adjust the quality/size balance before converting when the target format supports compression.
Will transparent areas survive the conversion to FITS?
Transparency is kept whenever FITS actually supports an alpha channel. If the target format has none (like JPG), transparent areas are flattened onto a white background — that is a property of the format, not of this tool.
Can I convert several CUR files at once?
Yes — drop as many files as you like into the tool and they are converted in one batch. When more than one file comes out, everything is bundled into a ZIP for a single download.