Convert FIT to CAL

Stop converting FIT files one by one. reaConverter processes entire folders to CAL automatically — just drag, drop, and click Convert.

Online converters too slow for your FIT files? reaConverter works locally and handles unlimited batches. All processing runs locally on your PC, so your files stay private and secure.

1. Download and Install reaConverter

First, grab reaConverter from the download button below. Installation is fast, and the software runs offline — no account or signup needed. reaConverter also includes editing tools: resize, crop, rotate, and more.

Install reaConverter

2. Load your FIT files

Open reaConverter and add your FIT files. You can load individual files, entire folders, or even nested subfolders.

Drop your FIT files into the window or use File menu to browse and select folders.

3. Select CAL as output format

Choose CAL as the target format. Pick a destination folder or let reaConverter save files alongside the originals.

4. Start FIT to CAL conversion

Hit Convert and let reaConverter do the work. The progress window shows status for each file in real time.

After conversion, find your CAL files in the output folder. Click 'Show converted files' to open it directly.

FIT to CAL Converter

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

Download Free Trial

Do more with your images

Converting FIT images for use in a larger project? With reaConverter, you can convert, edit, and enhance your images in one streamlined process.

Our range of editing options includes such image processing actions as Resize, Rotate, Crop, Color Replace, Watermarks and more. Adjust actions include RGB, HLS, HSV, Brightness and Contrast. Auto-processing options are also available, such as auto-rotate and auto-crop.

Image editing tools

User Reviews

Average User Rating:
Last updated on January 25, 2026

"reaConverter perfectly processes FIT files from our observatory telescopes into TIFFs while preserving all celestial metadata and sensor calibration data. Finally, we can batch-convert night-sky captures without losing a single photon of data fidelity!"

Prof. William S. Davis

Satisfied Customer

"An excellent program! I use it regularly in my work - it supports nearly every file format imaginable. The interface is intuitive and runs flawlessly every time."

Roger Cook

Happy User

"For agencies handling confidential data, reaConverter eliminates cloud-upload risks while delivering unmatched conversion reliability. Our team uses it both in-office and remotely with identical results."

Jamal Bailey

Satisfied Customer

"Our volunteer team uses reaConverter to prepare images for fundraising campaigns. The learning curve was minimal, and the results are professional-grade. The customer support team even helped us customize a workflow — fantastic service!"

Jason P. Bailey

Non-Profit Coordinator

"We deployed reaConverter across our department to standardize file formats for our archives. The command-line support and automation features integrated perfectly into our systems. Stellar performance and zero crashes—it just works."

David R.

IT Solutions Architect

"So simple! I just needed to convert a couple of files to another format, and for such a straightforward task, the online converter worked perfectly — delivering the files I needed in no time. Excellent service!"

Kenneth D. Carter

Satisfied Customer

FIT to CAL Conversion: FAQ

Can reaConverter convert FIT to CAL?

Yes! reaConverter instantly converts .fit to .cal 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.

What is reaConverter used for?

reaConverter is a software program used for converting images and other types of files from one format to another. It supports a wide range of file formats and allows users to convert multiple files at once, making it a valuable tool for graphic designers, photographers, and other professionals who work with digital images. reaConverter also includes features for resizing, cropping, and editing images, along with batch processing capabilities that help automate repetitive tasks.

Can I convert FIT to CAL online?

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

How can I turn FIT files into CAL on my computer?

The best way to change FITs to CALs 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 FIT to CAL.

How can I automate FIT to CAL 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 FIT files to CAL using the command prompt?

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

What else can I do with reaConverter?

Set file date Convert RAW formats Convert CAD formats Set picture bit depth Change format settings