FITS vs TIFF
A detailed comparison of FITS Astronomical Image and TIFF Image — file size, quality, compatibility, and which format to choose for your workflow.
FITS Astronomical Image
Raster & Vector ImagesFITS (Flexible Image Transport System) is the standard digital file format in astronomy for storing images, tables, and metadata from telescopes and satellites. It supports multi-dimensional arrays and extensive header metadata for scientific observation records.
About FITS filesTIFF Image
Raster & Vector ImagesTIFF is a flexible, high-quality image format widely used in publishing, printing, and professional photography. It supports multiple compression methods and color spaces including CMYK.
About TIFF filesStrengths Comparison
FITS Strengths
- Self-documenting — every file carries complete observational metadata.
- Lossless — bit-exact storage of detector readouts.
- Stable since 1981 with zero breaking changes.
- Mandatory for professional astronomy — every research publication uses it.
- Open standard endorsed by IAU.
TIFF Strengths
- Lossless by default — no generation loss on successive edits and saves.
- Supports any bit depth (1 to 32 bits per channel), any color model, any number of channels.
- Extensible tag system means vendor-specific data survives alongside standard tags.
- Multi-page containers are perfect for scanned documents, faxes, and DICOM-like stacks.
- Industry-standard for archival, museums, scientific imaging, and high-end print prepress.
Limitations
FITS Limitations
- Niche — used almost exclusively in astronomy.
- File sizes are large (no default compression).
- Not a display format outside specialized viewers (DS9, AstroBin).
- Consumer imaging apps don't understand FITS.
TIFF Limitations
- File sizes are huge compared to JPEG/WebP/AVIF — often 10-30× larger.
- Not a web format — no browser displays TIFF natively.
- Ambiguous spec areas mean some TIFFs only open correctly in the tool that created them.
- Weak animation support — designed for still imagery.
Technical Specifications
| Specification | FITS | TIFF |
|---|---|---|
| MIME type | image/fits | image/tiff |
| Extensions | .fits, .fit, .fts | .tif, .tiff |
| Standard | IAU-endorsed FITS 4.0 (latest revision) | TIFF 6.0 (1992); BigTIFF extension for 64-bit offsets |
| Header records | 80-character ASCII cards | — |
| Encoding | IEEE big-endian integers and floats | — |
| Max file size | — | 4 GB (TIFF); 2^64 bytes (BigTIFF) |
| Compression options | — | None, LZW, Deflate, JPEG, CCITT G3/G4, PackBits, JBIG |
Typical File Sizes
FITS
- Backyard-telescope CCD shot (5 MP) 10-30 MB
- Hubble WFC3 single exposure ~65 MB
- JWST NIRCam full detector ~650 MB
TIFF
- Scanned A4 page (300 dpi, B&W) 100-300 KB
- Scanned A4 page (600 dpi, color) 15-40 MB
- Print-quality magazine photo 30-150 MB
- Satellite GeoTIFF tile 50 MB - 5 GB
Ready to convert?
Convert between FITS and TIFF online, free, and without installing anything. Encrypted upload, automatic deletion after 60 minutes.
Frequently Asked Questions
FITS (FITS Astronomical Image) is an image format used to store raster graphics — a two-dimensional grid of pixels describing a picture. It is part of the raster & vector images family and designed around a specific trade-off between file size, visual fidelity, and feature support (transparency, colour depth, compression type). Photographers, web designers, and content creators choose FITS when its particular strengths match the publishing target.
FITS (FITS Astronomical Image) is an image formato used to store raster graphics — a two-dimensional grid of pixels describing a picture. It is part of the raster & vector images family e designed around a specific trade-off between tamanho do arquivo, visual fidelity, e feature support (transparency, colour depth, compressão type). Photographers, web designers, e content creators choose FITS when its particular strengths match the publishing target.
Most desktop photo viewers (Windows Photos, macOS Preview, GIMP, Photoshop, Affinity Photo) open FITS natively. On mobile, iOS Photos and Google Photos display FITS in the gallery when supported by the OS. If the format is rare or new, convert to JPG or PNG first — both are universally readable — using our FITS to JPG or FITS to PNG converter.
Most desktop photo viewers (Windows Photos, macOS Preview, GIMP, Photoshop, Affinity Photo) abrir FITS natively. On mobile, iOS Photos e Google Photos display FITS no gallery when suportado por the OS. If the formato is rare ou new, converter to JPG ou PNG first — both are universally readable — usando our FITS to JPG ou FITS to PNG converter.
Upload the FITS to KaijuConverter and pick a target format (JPG, PNG, WebP, HEIC, TIFF, BMP, SVG, PDF). The conversion runs in the browser via ImageMagick and returns a download in seconds. No account or installation required; both input and output delete automatically within two hours.
It depends on the task. JPG is the smallest file size for photographs; PNG is lossless with transparency; FITS has its own niche that may favour colour depth, animation, or encoding efficiency over one or both of those. For the final web publish, test all three and measure file size plus visible quality on real content.