Convert BGL to XML

What the BGL format is

BGL is Babylon’s compiled binary glossary format. Babylon dictionary-authoring tools package headwords, definitions, formatting, pronunciation information, and sometimes images or audio into BGL files.

BGL files are commonly distributed as downloaded dictionaries or language packs. Babylon and readers such as GoldenDict can open many BGL files, but BGL is not a general-purpose editable format and its internal data is not ordinary XML.

What the XML format is

XML represents structured data with readable elements and attributes. XML dictionary data can be inspected in a text editor, queried with XPath, transformed with XSLT, imported into a database, or adapted for another dictionary application.

There is no universal dictionary XML schema. XDXF (XML Dictionary eXchange Format) is the usual XML-based target for dictionary conversion, but the receiving application may require its own elements for entries, examples, formatting, audio, or images. Confirm the required schema before converting.

How to convert the dictionary

PyGlossary is the most practical local option for supported Babylon BGL files. It reads the binary glossary and writes XDXF without uploading dictionary data to a web service.

1. Install a current Python version, then install PyGlossary with python -m pip install pyglossary.
2. Put the source file in a working directory, such as english.bgl.
3. Run pyglossary english.bgl english.xdxf. PyGlossary normally detects the input and output formats from the filename extensions.
4. If detection fails, select Babylon as the input format and XDXF as the output format explicitly in PyGlossary’s graphical interface or command options.
5. Open english.xdxf in an XML-aware editor and test it in the destination application. Check representative headwords, markup, non-Latin text, links, and metadata rather than relying only on whether the file opens.

The output is XDXF content, which is XML-based, but it is not automatically compatible with every application that accepts a file named .xml. If the destination requires a proprietary schema, transform the XDXF with an XSLT stylesheet or a custom script. Renaming english.xdxf to english.xml changes only the filename extension and does not change the schema.

GoldenDict and similar dictionary readers are useful for testing the source glossary, but they are generally readers rather than BGL-to-XML export tools. No broadly reliable online converter should be assumed for this format; specialist web services may not support the relevant BGL variant or the destination schema. Keep conversion local, especially for copyrighted dictionaries, unless a service explicitly documents Babylon BGL input and the required XML output.

Quality and compatibility limits

Basic headwords and definitions usually transfer, but conversion can lose or alter proprietary formatting, embedded images, audio, hyperlinks, pronunciation data, licensing metadata, and compressed resources. The result also depends on the BGL version and the converter’s support for that dictionary’s internal structures.

Some BGL files use variants, packaging, or protection that PyGlossary cannot decode. A failed read requires a compatible converter version, a different copy of the source, or an export from the original Babylon authoring project; changing the extension cannot repair an unsupported file.

Preserve the original BGL and compare entry counts before and after conversion. If media is essential, verify that the output contains usable references or extracted files rather than assuming that every resource was preserved.