XLSX to FTS Converter

Convert XLSX to FITS image — free online

Drop files here. 1 GB maximum file size or Sign Up
to
Facebook Amazon Microsoft Tesla Nestle Walmart L'Oreal

Scientific Format

FTS (FITS) is the standard for astronomical and scientific imaging. Your XLSX data enters a format recognized by research tools.

Quick Processing

Server-side conversion produces the FTS file rapidly. No local scientific software installation required.

Data Safety

Your uploaded XLSX is erased immediately. Generated FTS files are purged within 24 hours automatically.

How to convert XLSX to FTS

1

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

2

Choose fts or any other format you need as a result (more than 200 formats supported)

3

Let the file convert and you can download your fts file right afterwards

About formats

XLSX is the default spreadsheet format for Microsoft Excel since Office 2007, based on the Office Open XML (OOXML) standard published as ECMA-376 and adopted as ISO/IEC 29500. An XLSX file is a ZIP archive containing XML documents that describe workbook structure, sheet data, styles, shared strings, formulas, charts, pivot tables, and relationships between components. Each worksheet is stored as a separate XML part where cells are organized by row and column references with typed values and style indices. The XML foundation enables programmatic spreadsheet creation and manipulation using libraries like openpyxl (Python), Apache POI (Java), and ClosedXML (.NET) without requiring Excel. XLSX dramatically expanded capacity compared to XLS: over 1 million rows and 16,384 columns per sheet, enabling use cases previously impossible in the binary format. One advantage is openness and cross-platform support — the documented OOXML specification enables implementation by LibreOffice Calc, Google Sheets, Apple Numbers, and numerous specialized tools. Built-in ZIP compression is another practical strength: XLSX files are typically 50-75% smaller than equivalent XLS files, and the modular XML structure improves data recovery when files are partially corrupted. The format supports modern Excel features including structured tables, slicers, sparklines, Power Query connections, and real-time co-authoring. XLSX has become the standard format for spreadsheet data interchange across business, scientific, and government domains.
Developer: Microsoft
Initial release: January 30, 2007
FTS is a file extension for the Flexible Image Transport System (FITS), the standard data format used in astronomy since 1981 when it was defined by Don Wells, Eric Greisen, and R.H. Harten at the National Radio Astronomy Observatory, and subsequently endorsed by the International Astronomical Union in 1982. FITS was designed from the outset as a self-describing archival format: each file begins with one or more 2880-byte header blocks containing ASCII keyword-value pairs that describe the data's dimensions, coordinate system, observation parameters, and provenance, followed by data blocks in a variety of numeric types — 8/16/32/64-bit integers and 32/64-bit IEEE floating-point values. FITS supports multi-dimensional arrays (images, data cubes, hypercubes), binary tables for catalog data, and ASCII tables, with multiple Header/Data Units (HDUs) that can coexist in a single file. The format handles specialized astronomical data: spectral cubes, radio interferometry visibilities, multi-extension mosaic images from CCD arrays, and time-series photometry. One advantage is scientific rigor: FITS mandates that all metadata needed to interpret the data physically — coordinate transformations (WCS), photometric calibration, telescope and instrument parameters — travels with the file, eliminating the metadata-loss problem that plagues general-purpose image formats in scientific contexts. The format's longevity and institutional backing is another strength — virtually every observatory, space telescope (Hubble, James Webb, Chandra), and astronomical software package (DS9, IRAF, Astropy) uses FITS as its primary data format.
Developer: NASA / IAU
Initial release: 1981

Frequently Asked Questions

Why convert XLSX to FTS?

FTS (FITS) is a scientific data format used in astronomy — converting renders your spreadsheet data in a format tools like DS9 read.

What opens FTS files?

SAOImageDS9, FITS Liberator, Astropy (Python), GIMP (with plugin), and other astronomical software support the FITS format.

Is FTS used outside astronomy?

FITS is primarily an astronomy standard but also appears in medical imaging and scientific data archiving contexts.

Is the conversion free?

Convertio offers free basic conversions. Premium plans extend limits for scientific and research workflows.

Can I convert from any platform?

Yes — Convertio runs in any browser on any OS. No specialized scientific software is needed for the conversion step.

Is my data protected?

Uploaded XLSX is deleted after conversion. FTS outputs are removed within 24 hours from Convertio servers.

XLSX to FTS Quality Rating

5.0 (3 votes)
You need to convert and download at least 1 file to provide feedback!