Withdata DataFileConverter converts YAML (*.yaml, *.yml) files to Fixed-Width Text locally — single file, batch, or merge multiple YAML files into one Fixed-Width Text. Nested YAML mappings are flattened into dotted column names. 100% local, secure, and cross-platform.

YAML is a human-readable data serialization format.

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Why Choose Withdata YAML to Fixed-Width Text Converter?

🔒 100% Local & Secure

YAML files are read and converted on your own computer. Nothing is uploaded to any cloud server.

⚡ Fast Streaming Conversion

Large YAML files are processed in streaming mode with low memory usage — millions of rows within a minute.

📁 Batch & Merge

Batch convert many YAML files to Fixed-Width Text files, or merge multiple YAML files into one Fixed-Width Text.

🔄 Nested YAML → Dotted Columns

Nested mappings become address.city-style column names; sequences and block scalars are expanded automatically.

🖥 Windows, macOS, Linux

Native builds for Windows, macOS and Linux, with a step-by-step GUI wizard and a command line interface.

⏱ CLI & Scheduled Tasks

Save a conversion session and run it automatically from Windows Task Scheduler or crontab.

Full Feature Comparison

Feature	Supported details
Input source	Local YAML (`.yaml`, `.yml`), batch YAML, merged YAML
Output format	Fixed-width text with detected or custom column widths
Conversion mode	Single file · merge many YAML files into one Fixed-Width Text · batch (one to one)
Running mode	GUI wizard · command line · scheduled tasks
Source options	Dotted column names for nested mappings, row source, encoding
Output options	Column mapping, encoding, date format, empty value handling
Platform	Windows, macOS, Linux (native, 64-bit)

All YAML to Fixed-Width Text Conversions You Need

Single YAML file → Fixed-Width Text file, step by step in the GUI wizard
Batch convert multiple YAML files → multiple Fixed-Width Text files
Convert YAML to Fixed-Width Text in the command line, and run it as a scheduled task
All YAML conversion tools and all Fixed-Width Text conversion tools

YAML to Fixed-Width Text Notes

A top-level sequence of mappings is read as a table — each mapping becomes one row.
Nested mappings are flattened into dotted column names, e.g. address.city, address.zip.
Block scalars (|, >) are read as multi-line text.
Both .yaml and .yml files are accepted; UTF-8 (with or without BOM) is detected automatically.
Not supported: anchors and aliases (& / *), tags (!!) and multi-document files (---).
Output column widths are detected from the data (measured width + 15% slack, at least 2 and at most 15 extra characters), or set manually.

How to Convert YAML to Fixed-Width Text (4 Steps)

Open Withdata DataFileConverter and select YAML as the input type and Fixed-Width Text as the output type.
Load your YAML data — a single file, a folder / list of files for batch conversion, or several files to merge into one.
Check the preview table, then adjust the source options and the output options.
Click Convert — the Fixed-Width Text output is written in seconds. Save the session if you want to run it again from the command line.