HDR to SUN — Format Comparison & Online Converter
Fast, instant HDR to SUN conversion. No signup required. Just drop your .hdr file and get .sun in seconds.
Batch Settings
About HDR to SUN Conversion
HDR (introduced 1985) and SUN are both image formats, but they differ in important ways. HDR (Radiance) is a high-dynamic-range image format used in lighting and rendering. SUN is a widely used file format.
When you convert HDR to SUN, the goal is to convert between formats quickly. Converting HDR to SUN maintains high quality with CocoConvert's optimised encoder settings. Understanding these technical differences helps you choose the right format for your workflow.
Your HDR file is decoded and re-encoded as SUN. The conversion involves 4 steps: (1) your hdr file is uploaded and validated, (2) the file is decoded (parsed into its raw data), (3) the data is re-encoded in sun format, (4) the converted file is ready for download.
CocoConvert's converter handles the entire pipeline server-side using FFmpeg, Sharp, and qpdf — battle-tested libraries used by streaming platforms and enterprise tools. Files are encrypted in transit and deleted within 24 hours.
This conversion is ideal when you When you need a SUN file. For the opposite direction, CocoConvert also supports SUN to HDR conversion.
How to Convert HDR to SUN
- 1
Upload .hdr file
Select your HDR file by dragging it to the upload zone or using the file picker. Batch upload is available for multiple files.
- 2
Choose .sun
Set SUN as the output format. The converter uses optimal settings based on the HDR→SUN conversion profile.
- 3
Convert
The server-side engine decodes your HDR file and re-encodes it as SUN. Processing time depends on file size and complexity.
- 4
Download result
Grab your converted .sun file. Multiple output files can be downloaded together.
What Happens When You Convert HDR to SUN
Your HDR file is decoded and re-encoded as SUN.
Your HDR 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
HDR
.hdr file
| Extension | .hdr |
| MIME Type | image/vnd.radiance |
| Category | Image |
SUN
.sun file
| Extension | .sun |
| MIME Type | image/x-sun-raster |
| Category | Image |
Should You Convert HDR to SUN?
When to Convert
- ✓When you need a SUN file
Frequently Asked Questions
What is the difference between HDR and SUN?
HDR (Radiance) is a high-dynamic-range image format used in lighting and rendering. SUN is a widely used file format.
Does HDR to SUN conversion affect quality?
Converting HDR to SUN maintains high quality with CocoConvert's optimised encoder settings.
Which format has better compression, HDR or SUN?
HDR uses lossless compression. SUN is widely supported. The better choice depends on whether you prioritize file size or quality.
How long does HDR to SUN conversion take?
Most conversions finish in seconds. Larger files or complex image content may take 10–30 seconds. CocoConvert processes files in parallel for batch jobs.
Is HDR or SUN better for long-term storage?
HDR is better for archival since it's lossless.
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