Open FITS files online

FITS is the astronomy standard for telescope and satellite images and tabular data.

Guide only — This browser cannot render the format yet; the page lists compatible software and libraries.

Guide only

This browser cannot render the format yet; the page lists compatible software and libraries.

Besides this free online viewer, you can open FITS (astronomy) files in desktop apps such as SAOImageDS9, FITS Liberator — but here all you need is a web browser.

Sample files for FITS (astronomy)

This browser cannot render the format yet; the page lists compatible software and libraries.

What is a FITS file?

FITS is the astronomy standard for telescope and satellite images and tabular data. The .FITS extension identifies a Flexible Image Transport System file, which is served with the application/fits media type.

Besides this free online viewer, you can open FITS (astronomy) files in desktop apps such as SAOImageDS9, FITS Liberator — but here all you need is a web browser.

Quick facts

FormatFITS (astronomy) — Flexible Image Transport System
File extensions.fits .fit
MIME typeapplication/fits
DeveloperNASA / IAU
CategorySpecialised
Also opens inSAOImageDS9, FITS Liberator

100% private — files never leave your browser.

Software and libraries that can open a FITS file

This browser cannot render the format yet; the page lists compatible software and libraries.

Frequently asked questions

What is a .FITS file?

This browser cannot render the format yet; the page lists compatible software and libraries.

What programs open FITS files?

On the desktop, FITS files typically open in SAOImageDS9, FITS Liberator. Online, this page opens them in any modern browser — nothing to download.