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