YAML Document Stream Splitter & Merger
About YAML Multi-Document Splitter / Merger
YAML Multi-Document Splitter / Merger handles YAML streams that use --- markers to carry several independent documents in one file.
How it works
Split into self-contained parts
Split mode parses every YAML 1.2 document and returns a JSON manifest containing a stable filename, UTF-8 byte count and standalone YAML text for each part.
Merge loose fragments
Merge mode accepts documents separated by a line containing ===, or normalizes an existing YAML stream. Every output document receives an explicit --- start marker.
Optional explicit endings
Enable end markers to append ... after each document for systems that prefer fully explicit stream boundaries. Comments remain attached through syntax-tree serialization.
Frequently asked questions
Why use === between merge fragments?
It provides an editing delimiter that cannot be mistaken for YAML's actual --- document start marker. The delimiter itself is not included in output.
Can merge mode accept an existing --- stream?
Yes. Without === lines, the input is parsed as a normal YAML stream and re-emitted with normalized boundaries.
Are directives and comments retained?
Comment text and YAML nodes are retained. Stream markers and surrounding whitespace are normalized by the serializer.
Sources & last verified
The behaviour of this tool and the claims on this page were checked against the specifications below on . Everything runs in your browser, so the output you see is exactly what the engine produced.
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