uFits

See FITS in your Finder.

Select a file, press Space. Images, plots, tables and headers, at once.

Install: paste this in Terminal
curl -fsSL https://github.com/lmytime/uFits/releases/latest/download/install.sh | sh

macOS 11 or later Apple silicon and Intel 1 MB uFits.dmg

Observations
Select See it

Everything inside, at a glance.

ngc4535.fits
3072 × 2048 · float32Auto stretchImageHeader

Auto stretch

linear and min–max, a click away
ngc4535.fits
100%ImageHeader

Zoom to the pixel

pinch · ⌥-click · ⌘-scroll
tess-lc.fits
3600 rowsPlotTable

Spectra and light curves

gaia-cluster.fits
2500 rowsPlotTable

Catalogs on the sky

RA and Dec
ngc2403-hi.fits
1 / 32

Step through cubes

survey.fits
1,000,000 rows × 4 columnsPlotTableHeader

A million rows

no wait · ⌘C copies
ngc4535.fits
ImageTableHeader

Every header card

lined up · ⌘F finds

FITS, XISF, ASDF and X-ray files

compressed ones too

Light by day, Dusk by night

the icon follows macOS 26
ngc4535.fits
3072 × 2048 · float32Update availableImageHeader

Updates itself

in a few seconds

Get uFits

Paste this in Terminal
curl -fsSL https://github.com/lmytime/uFits/releases/latest/download/install.sh | sh

uFits.dmg macOS 11 or later Apple silicon and Intel Free and open source