How to Convert SFW to FITS — Quick & Free
Fast, instant SFW to FITS conversion. No signup required. Just drop your .sfw file and get .fits in seconds.
Batch Settings
About SFW to FITS Conversion
Short answer: yes, you can convert SFW to FITS online for free, and quality is well preserved with the right settings. Just upload your .sfw file to CocoConvert, pick FITS as the output, and click Convert. The whole process takes seconds.
Now for the details. SFW is a widely used file format. FITS is a widely used file format. Converting between these two formats lets you convert between formats quickly.
Your SFW file is decoded and re-encoded as FITS. Converting SFW to FITS maintains high quality with CocoConvert's optimised encoder settings.
CocoConvert runs entirely online — no software to install, no account to create. Your files are encrypted during upload (TLS), processed on isolated servers in Germany, and permanently deleted after 24 hours. It works in Chrome, Safari, Firefox, Edge, and all mobile browsers.
Need to convert more than one file? Free users can do 5 per hour. Pro gets 100 per hour with files up to 5 GB each.
How to Convert SFW to FITS
- 1
1. Upload SFW
Drop your .sfw file onto the page (or tap "Browse" on mobile). Add multiple files for batch conversion.
- 2
2. Select FITS
Choose .fits from the output dropdown. Settings are pre-configured for best results.
- 3
3. Convert
One click. The server handles all the heavy lifting using FFmpeg and Sharp.
- 4
4. Download
Your .fits file is ready. Download it directly or get all files as a zip archive.
What Happens When You Convert SFW to FITS
Your SFW file is decoded and re-encoded as FITS.
Your SFW file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in FITS format
The converted file is ready for download
Format Comparison
SFW
.sfw file
| Extension | .sfw |
| MIME Type | image/x-sfw |
| Category | Image |
FITS
.fits file
| Extension | .fits |
| MIME Type | image/fits |
| Category | Image |
Should You Convert SFW to FITS?
When to Convert
- ✓When you need a FITS file
Frequently Asked Questions
Is SFW to FITS conversion free?
Yes. CocoConvert offers free SFW to FITS conversion with generous daily limits — 25 minutes of processing time and up to 5 files per hour (250 MB each). Pro plans remove these limits.
How fast is SFW to FITS conversion?
Most files convert in 2–10 seconds depending on size. Large image files may take 30 seconds. Batch jobs process in parallel for maximum speed.
What happens to my files after conversion?
Your uploaded SFW file and the converted FITS file are both automatically deleted from our servers within 24 hours. They are never shared, sold, or analysed.
Does converting SFW to FITS lose quality?
Converting SFW to FITS maintains high quality with CocoConvert's optimised encoder settings.
Can I convert FITS back to SFW?
Yes, CocoConvert supports FITS to SFW conversion as well. However, if the original conversion involved lossy compression, converting back won't recover the lost data.
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