GeoTIFF to FITS Converter
Processing entirely on your device — large files may take a moment.
Convert FITS frames to PNG or JPG to preview telescope data, or pack them into a ZIP for sharing. If your files are still in GeoTIFF format, this page is the shortcut: GeoTIFF is a TIFF that carries its geography: embedded tags map every pixel to real-world coordinates and projection (EPSG codes), making it the standard interchange format for satellite imagery, drone orthomosaics and GIS raster layers.
This converter runs entirely in your browser using WebAssembly — your files never leave your device, nothing is uploaded, and there are no watermarks, sign-ups or queues. Drop in several files at once to convert them as a batch.
How to convert GeoTIFF to FITS
- 1
Select your files
Drag & drop your GeoTIFF files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to FITS". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted FITS file individually, or grab everything at once as a ZIP archive.
About the GeoTIFF format
GeoTIFF answers a question plain TIFF cannot: where on Earth is this pixel? It is a regular TIFF image plus a set of metadata tags — ModelPixelScale and ModelTiepoint map pixel rows and columns to projected coordinates, and GeoKeyDirectory stores the projection itself as EPSG codes (UTM zones, Web Mercator, national grids). The result is the de-facto standard for satellite scenes, Landsat/Sentinel downloads, drone orthomosaics, elevation models and every GIS raster layer that has to survive being emailed between software.
Because the geography lives in TIFF tags, the pixel data is ordinary imagery — which means converting GeoTIFF to PNG, JPG or WebP is really just decoding a TIFF and dropping the map metadata. That is exactly what you want for previews: a web page, a slide deck or a chat message has no idea what an EPSG code is, but it will happily show the image. What you lose in the conversion is the georeference itself, so keep the original .tif whenever the file feeds back into QGIS or ArcGIS.
+Strengths
- ✓Self-describing: image + coordinates + projection in one file
- ✓Read by every GIS tool (QGIS, ArcGIS, GDAL, Google Earth)
- ✓Supports 16-bit, float, multi-band and tiled storage
!Limitations
- −Converting to PNG/JPG discards the georeference
- −Files are large — TIFF has no strong compression by default
- −Overkill for images that never touch a map
About the FITS format
FITS (Flexible Image Transport System) has carried professional astronomy data since 1981: every file opens with a plain-text header that records telescope, instrument, exposure, filters and world coordinates, followed by raw pixel arrays — often 16-bit or float, sometimes data cubes.
Values can be negative or far above display range, so FITS never looks right in a photo viewer. Converting to PNG applies a simple scaling pass that reveals the nebula or galaxy in the numbers — good for previews, while science pipelines keep the original.
+Strengths
- ✓Self-documenting science headers
- ✓High bit depth (16/32-bit, float)
- ✓The standard of every observatory
!Limitations
- −Not display-ready
- −Files are large and uncompressed
Why convert GeoTIFF to FITS?
Converting makes sense where the strengths of FITS meet what GeoTIFF cannot give you. Self-documenting science headers Meanwhile Converting to PNG/JPG discards the georeference One pass through the converter above puts your file on the right side of that trade-off.
Frequently asked questions
Is this GeoTIFF to FITS converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Will I lose quality converting GeoTIFF to FITS?
No — FITS is a lossless format, so every pixel of the converted image matches your original GeoTIFF file. You can also adjust the quality/size balance before converting when the target format supports compression.
Can I convert several GeoTIFF files at once?
Yes — drop as many files as you like into the tool and they are converted in one batch. When more than one file comes out, everything is bundled into a ZIP for a single download.
Will transparent areas survive the conversion to FITS?
Transparency is kept whenever FITS actually supports an alpha channel. If the target format has none (like JPG), transparent areas are flattened onto a white background — that is a property of the format, not of this tool.