What is the BXL file format?
A .bxl file is an Ultra Librarian Binary Component Library file - a proprietary binary container that bundles the complete CAD data for a single electronic component: its schematic symbol (pin names, logic types, bus groupings), PCB land pattern/footprint (copper pad geometry, silkscreen, courtyard), and optionally a 3D STEP model for mechanical clearance checking.
BXL stands for Binary eXchange Language. The format was created by Accelerated Designs, Inc. as a vendor-neutral delivery vehicle that semiconductor manufacturers use to distribute accurate, pre-verified component data to PCB designers, regardless of which EDA platform the designer uses. Texas Instruments, Analog Devices, Microchip, NXP, STMicroelectronics, and Silicon Labs are among the many chip vendors that publish .bxl files for their parts on distributor and manufacturer component portals.
The free Ultra Librarian Reader desktop application imports .bxl files and exports to over 20 EDA-specific library formats, including Altium Designer .IntLib, Cadence Allegro, Mentor PADS, OrCAD, and Zuken CADSTAR. A browser-based Ultra Librarian Online Reader is also available for tool-free conversion. KiCad users can use third-party converters such as the BXL Converter at convert.guru.
Individual .bxl files range from about 5 KB (simple passive components) to 500 KB (large ICs with detailed 3D models). The binary format is fully proprietary and undocumented; no other EDA tool can parse .bxl directly without Ultra Librarian.
Accelerated Designs was acquired by Altium in 2019, and Ultra Librarian continues as an actively maintained product under Altium's umbrella.
Security & safety
RISK: LOWPassive binary data file containing CAD geometry. Not executable; no known malware vector. Download only from official semiconductor manufacturer pages or the Ultra Librarian platform.
Format details
in a nutshell- Turbo-Basic XL source code (Atari 8-bit) - A completely unrelated use: Turbo-Basic XL, a BASIC dialect for Atari 8-bit computers, also uses .bxl for source files - a coincidence with no connection to PCB/CAD.
Programs that open BXL files
Windows3 apps
Ultra Librarian Reader (free)
Free Import the .bxl file, then use File → Export to choose your EDA tool format (Altium, OrCAD, Cadence, PADS, etc.) and export the symbol and footprint.
Ultra Librarian Online Reader
Free Upload the .bxl to the web-based reader at ultralibrarian.com to preview and download converted library files without installing software.
BXL Converter (convert.guru)
Free Online tool to convert .bxl to .LBR (KiCad), .OLB (OrCAD), .IntLib (Altium), .MOD (PCB footprint) formats. 
macOS1 app
Ultra Librarian Online Reader
Free Browser-based - upload the .bxl and download in your EDA tool format; no installation required. 
Linux1 app
Ultra Librarian Online Reader
Free Browser-based conversion; the desktop Ultra Librarian Reader is Windows-only. Technical details
deep spec| Format type | Proprietary binary PCB component library container |
| Name expansion | BXL = Binary eXchange Language |
| Encoding | Binary, little-endian (Windows-origin format) |
| Typical file size | 5 KB - 500 KB per component |
| Content per file | Schematic symbol (pin definitions, logic types) + PCB land pattern/footprint (copper pads, silkscreen, courtyard) + optional 3D STEP model |
| Distribution model | Published by semiconductor manufacturers (TI, Analog Devices, Microchip, NXP, STMicroelectronics, Silicon Labs) as vendor-neutral component data for PCB designers |
| Export targets | Ultra Librarian Reader exports to 20+ EDA formats: Altium Designer, Cadence Allegro, Mentor PADS, OrCAD, Zuken CADSTAR, and others |
| Web access | Ultra Librarian Online Reader (browser-based) allows import and export without installing desktop software |
| Spec status | Fully proprietary, undocumented format - no public specification and no third-party parser |
| Developer history | Created by Accelerated Designs, Inc.; acquired by Altium in 2019; Ultra Librarian brand continues under Altium |
| Platform | Windows (Ultra Librarian desktop); web browser (Ultra Librarian Online Reader) |
| Released | circa 2005-2010 (Ultra Librarian product era) |
| Latest version | Current as of 2026 - actively maintained by Accelerated Designs / Altium |
| Specification | www.ultralibrarian.com |
BXL conversions
Community Q&A
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