How to Convert X3F to FTS — Quick & Free
Fast, instant X3F (SIGMA) to FTS conversion. No signup required. Just drop your .x3f file and get .fts in seconds.
Batch Settings
About X3F (SIGMA) to FTS Conversion
Short answer: yes, you can convert X3F to FTS online for free, and quality is well preserved with the right settings. Just upload your .x3f file to CocoConvert, pick FTS as the output, and click Convert. The whole process takes seconds.
Now for the details. X3F is a widely used file format. FTS is a widely used file format. Converting between these two formats lets you convert between formats quickly.
Your X3F file is decoded and re-encoded as FTS. Converting X3F to FTS 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 X3F (SIGMA) to FTS
- 1
1. Upload X3F
Drop your .x3f file onto the page (or tap "Browse" on mobile). Add multiple files for batch conversion.
- 2
2. Select FTS
Choose .fts 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 .fts file is ready. Download it directly or get all files as a zip archive.
What Happens When You Convert X3F (SIGMA) to FTS
Your X3F file is decoded and re-encoded as FTS.
Your X3F file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in FTS format
The converted file is ready for download
Format Comparison
X3F (Sigma)
.x3f file
| Extension | .x3f |
| MIME Type | image/x-sigma-x3f |
| Category | Image |
FTS
.fts file
| Extension | .fts |
| MIME Type | image/fits |
| Category | Image |
Should You Convert X3F (SIGMA) to FTS?
When to Convert
- ✓When you need a FTS file
Frequently Asked Questions
Is X3F to FTS conversion free?
Yes. CocoConvert offers free X3F to FTS 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 X3F to FTS 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 X3F file and the converted FTS file are both automatically deleted from our servers within 24 hours. They are never shared, sold, or analysed.
Does converting X3F to FTS lose quality?
Converting X3F to FTS maintains high quality with CocoConvert's optimised encoder settings.
Can I convert FTS back to X3F?
Yes, CocoConvert supports FTS to X3F conversion as well. However, if the original conversion involved lossy compression, converting back won't recover the lost data.
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