ICO to FTS Converter

Free online ICO to FTS converter with instant results

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Full Resolution

Convertio extracts the highest resolution image from your ICO container and converts it to FTS — preserving maximum detail.

Works Everywhere

Convert ICO to FTS from any device — Windows, Mac, Linux, iOS, or Android. All you need is a browser and internet connection.

Instant Conversion

The ICO to FTS conversion engine processes files quickly — expect your download to be ready in just a few seconds after uploading.

How to convert ICO 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

ICO is the icon file format for Microsoft Windows), introduced with Windows 1.0 in 1985 and serving as the standard container for application icons, file type icons, and shortcut icons throughout the Windows ecosystem. An ICO file bundles multiple image variants within a single container — each at different sizes (16x16, 32x32, 48x48, 256x256, and others) and color depths (4-bit, 8-bit, 24-bit, 32-bit with alpha) — allowing Windows to select the most appropriate image for each display context, from tiny taskbar buttons to large desktop icons. The container structure consists of an ICONDIR header, an array of ICONDIRENTRY records describing each variant, and the image data itself. Since Windows Vista, ICO files support embedded PNG-compressed images for the larger sizes (typically 256x256), dramatically reducing file size while maintaining quality with full alpha transparency. One advantage is automatic size adaptation — Windows pulls the optimal resolution from the ICO container for each context (Explorer list view, desktop tile, Alt-Tab preview), ensuring crisp display without the application managing separate image files. The format's operating system-level integration is another core strength: ICO files serve as the identity mechanism for executables, file associations, and shortcuts across all Windows versions, and web browsers use favicon.ico for website identity in tabs and bookmarks. ICO creation and editing is supported by image editors like GIMP, Inkscape, and dedicated icon tools, and the format remains essential for Windows application development.
Developer: Microsoft
Initial release: 1985
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 ICO to FTS?

FITS format stores your icon as astronomical image data — used when icon-sized graphics need to be loaded into scientific analysis software.

What software reads FTS format?

Common options include SAOImage DS9, FITS Liberator, Aladin, AstroImageJ. The format has good support across major operating systems.

Can I use this on Mac and Linux?

The converter is entirely browser-based — it works on macOS, Linux, Windows, and any other platform with a modern web browser. No OS-specific software needed.

Is ICO to FTS conversion free?

Basic conversions are free on Convertio. Premium plans offer faster processing, larger file sizes, and higher daily conversion limits for heavier workloads.

Does ICO to FTS keep transparency?

If FTS supports transparency (like PNG or WEBP), the alpha channel from your ICO is preserved. Formats without transparency support fill with a solid background.

Is the conversion process fast?

ICO to FTS conversion usually finishes in a few seconds. Larger files may take slightly longer, but the cloud-based processing keeps things efficient.

ICO to FTS Quality Rating

5.0 (2 votes)
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