Browse Tools Top 100
FIT JPEG
File conversion

Convert FIT to JPEG

Verified by Adam B.· reviewed by FE Editorial ·updated Sep 1, 2026
QUICK ANSWER
Is it possible to convert FIT to JPEG?
Yes - FIT converts to JPEG.

Open the .fit in SAOImageDS9 (free), adjust the stretch in the Scale menu, then use File > Save Image > JPEG. XnView MP is a quicker alternative with automatic stretching but less control. No online tool handles FITS reliably.

1 programs
Also to JPEG: RGB · PNM · PGM

On this page

Tested on macOS, Windows & Linux
Last verified Oct 2026

More free converters

HEIC, PNG, WEBP, MP3 and more - every tool here is free.

Open the toolbox

Why convert FIT to JPEG?

FITS stores raw detector data at 16-bit or higher precision, far exceeding JPEG's 8-bit range. Converting to JPEG makes the image shareable and viewable anywhere outside astronomy software. The stretch applied before export determines which part of the tonal range becomes visible - different stretch choices produce noticeably different results from the same FITS file.

How to convert FIT to JPEG

SAOImageDS9 FREE

Open the .fit file, choose a stretch in the Scale menu (Linear, Log, or Sqrt) until the image looks correct, then export via File > Save Image > JPEG.

XnView MP FREE

Open the .fit directly in XnView MP, which applies an automatic stretch; use File > Export and choose JPEG with the desired quality setting.

ImageJ OPEN-SOURCE

Open the .fit in ImageJ, apply Brightness/Contrast adjustment, then use File > Save As > JPEG to export.

Programs that convert FIT

ImageJ

About these formats

.FIT Flexible Image Transport System (FITS) image

A .fit file is a FITS (Flexible Image Transport System) astronomy image - the standard scientific data format used by telescopes, astrophotography cameras, and research archives since 1981.…

Open .FIT details →
.JPEG JPEG Image

A JPEG file is a compressed photo or image - the same format as .jpg, byte for byte. Every operating system opens it without extra software: double-click and Windows Photos, macOS Preview,…

Open .JPEG details →

Quality & what to watch

  • JPEG is lossy - fine detail and faint astronomical structures will be degraded; export to 16-bit TIFF if the image needs further processing.
  • The stretch choice is not optional: different stretch functions (Linear, Log, Sqrt) produce visibly different images from the same FITS file.
  • FITS header metadata (telescope name, exposure time, coordinates) is not carried into the JPEG output; keep the original .fit if those values matter.

Frequently asked questions

Can I convert FIT to JPEG online?
No practical browser-based tool handles FITS; use SAOImageDS9 or XnView MP locally.
Will the JPEG look the same as the FITS image on screen?
Only if the JPEG was exported with the same stretch visible on screen at export time; the file captures the display state, not the full raw data range.
Are .fit, .fits, and .fts the same format?
Yes - if a tool refuses .fit, rename the file to .fits and try again; the binary format is identical.