Convert RAS to FITS

RAS to FITS made simple. Add files or folders, pick your settings, click Convert. reaConverter handles the rest — even thousands of files.

Tired of converting RAS files one at a time? reaConverter processes entire folders to FITS automatically. Handles large batches reliably without crashes or timeouts.

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RAS to FITS
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How to Convert Multiple RAS Files to FITS?

1. Download and Install reaConverter

reaConverter is a standalone Windows app — download, install, and start converting RAS files in under two minutes.

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Install reaConverter

2. Load your RAS files

Launch reaConverter and drop in your RAS files. The software queues everything for batch processing with consistent settings.

Add files by dragging them in, browsing folders, or using the right-click menu from Windows Explorer.

Load your RAS files into reaConverter

3. Select FITS as output format

Pick FITS as output format and choose the destination folder where you want to save new .fits files.

Select FITS as output format

4. Start RAS to FITS conversion

Then simply press the Convert button and your conversion will begin in no time!

Start Conversion

Once the conversion is complete, you can find your FITS files in the destination folder you selected.

RAS to FITS Converter

reaConverter offers the fastest, simplest solution for converting your RAS files into FITS in seconds - all files processed on your PC for maximum privacy and speed.

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Do more with your files

Converting RAS files for use in a workflow? reaConverter offers many ways to process files, so you can customize them according to your requirements.

Our range of editing options includes auto-processing options such as auto-rotate, auto-crop, watermarking and more. Change Color Space, copy Metadata, set DPI, manage ICC Profile, control Bit Depth.

Conversion features
Image editing

User Reviews

Average User Rating:
Last updated on January 25, 2026
"reaConverter makes FITS conversion incredibly easy. We batch convert astronomical images to standard formats for presentations and analysis, all automated through the command-line. It’s fast, reliable, and handles large datasets without issues."
Laura N.
Laura N.
Astrophysics Research Assistant
"Essential for our astroimaging pipeline! reaConverter perfectly handles FITS files from our research telescope, preserving all WCS coordinates and photometric data during batch conversion to TIFF. Now we process 100+ deep-sky exposures nightly without losing critical metadata for our exoplanet studies!"
Joseph Wilson
Joseph Wilson
Satisfied Customer
"Finally an app that actually opens my weird files! Saves me from format frustration daily."
Kyle Brooks
Kyle Brooks
Happy User
"This converter delivers exceptionally quick format conversions with reliable results every time."
Brian White
Brian White
Happy User
"Security was our top concern when evaluating file conversion tools. reaConverter’s offline mode and role-based access controls let us lock it down for sensitive environments. No unexpected network calls or bloat — just clean, fast conversions. Even passed our pen-testing scans without a hitch."
Marcus White
Marcus White
Healthcare IT
"An ultra-fast solution for minimizing file sizes. The entire conversion process takes just 3 minutes!"
Logan B.
Logan B.
Satisfied Customer

RAS to FITS Conversion: FAQ

What are RAS files?

The RAS file extension represents the CALS Raster File Format, a standard developed by the U.S. Department of Defense for the interchange of monochrome raster graphics. It is primarily used for storing high-resolution, black-and-white images such as engineering drawings, technical manuals, and scanned documents. CALS RAS files are typically used in military, aerospace, and government applications due to their consistency and archival suitability. The format supports compression and is optimized for printing and long-term storage.

What are FITS files?

The FITS (Flexible Image Transport System) format is a standard format used particularly for storing, transferring and processing scientific images from fields such as astronomy. FITS was first launched as an open standard in the early 1980s and has gone through several subsequent upgrades. FITS files contain not just images, but also data related to photometry and spatial calibration, and information about the origin of the image. Similar formats include FIT and FTS.

Can reaConverter convert RAS to FITS?

Yes! reaConverter instantly converts .ras to .fits with perfect quality preservation. With its batch processing feature, you can convert multiple files at once in just a few clicks. You can even convert images directly from Windows Explorer using the right-click menu — fast and convenient.

Can I convert RAS to FITS online?

If you only need to convert a few RAS files to FITS format, feel free to try our free online free online RAS to FITS converter — perfect for small batches with no installation needed!

How can I turn RAS files into FITS on my computer?

The best way to change RASs to FITSs on your PC is to install a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch files conversions, including conversion from RAS to FITS.

How can I automate RAS to FITS files conversion?

reaConverter supports all the most useful automation features such as right-click сonversion and Watch Folders for the most efficient automated files conversion in any software of this type.

Is there a way to convert RAS files to FITS using the command prompt?

reaConverter provides full access to all its features via Windows command line, including a high-performance command-line ras to fits converter for batch processing.

What else can I do with reaConverter?

Convert vector imagesConvert picture color spaceConvert DICOM imagesResize photoConvert CAD formats

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