YAML to NDJSON Converter

Transform YAML documents, configurations, and multi-document streams into compact Newline Delimited JSON lines.

At a glance

YAML to NDJSON Converter is a free web tool that converts YAML files and multi-document streams into Newline Delimited JSON (NDJSON / JSONL) records. Seamlessly splits '---' document boundaries into consecutive JSON lines. Automatically flattens YAML lists of objects into individual NDJSON records. Nothing is uploaded and no sign-up is needed — everything runs on your device.

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YAML to NDJSON Converter

100% Client-Side

Convert YAML multi-document streams and sequences into compact Newline Delimited JSON (NDJSON / JSONL) lines directly in your browser.

100% Client-Side Privacy Zero Server Uploads
Load Presets:
0 lines • 0 chars • 0 B output
YAML Input
0 lines
Generated NDJSON / JSONL 
# NDJSON output will appear here...

About YAML to NDJSON Conversion

Newline Delimited JSON (NDJSON / JSONL) stores structured records where every line is a discrete, valid JSON value. Converting YAML files, Kubernetes manifests, or server configurations into NDJSON allows high-throughput ingestion into tools like Elasticsearch, BigQuery, ClickHouse, Apache Spark, and modern log aggregators.

Array Unrolling

When your YAML input is a top-level sequence of objects (like - item: value), unrolling emits each item as an independent JSON line. This transforms configuration lists or product dumps into stream-friendly datasets.

Multi-Document Stream Support

Multi-document YAML files separated by --- boundary markers (such as multi-resource Kubernetes manifests or CI/CD pipelines) are seamlessly segmented and converted into consecutive JSON lines.

Why Use This YAML to NDJSON Converter?

100% Client-Side In-Browser Conversion: Private and secure. Logs and configs never leave your browser.
Multi-Document Stream Support: Seamlessly splits '---' document boundaries into consecutive JSON lines.
Array Unrolling Mode: Automatically flattens YAML lists of objects into individual NDJSON records.
Preserved Type Fidelity: Maintains strings, integers, floats, booleans, nulls, and nested sub-objects.

How to Use YAML to NDJSON Converter

1

Paste YAML or Load Preset

Paste your YAML content or multi-document stream into the editor, or choose from one of the built-in presets.

2

Configure Array Handling

Select whether to unroll array items into individual JSON lines or preserve each document as a single line.

3

Copy or Download NDJSON

Preview the resulting NDJSON lines in real time, copy them to your clipboard, or download as a .jsonl file.

Kubernetes YAML Manifest to NDJSON Stream

Converts multi-document Kubernetes YAML resources into a stream of Newline Delimited JSON lines.

YAML Input Source 
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: app-cfg
---
apiVersion: v1
kind: Service
metadata:
  name: app-svc
Generated NDJSON Output Processed 
{"apiVersion":"v1","kind":"ConfigMap","metadata":{"name":"app-cfg"}}
{"apiVersion":"v1","kind":"Service","metadata":{"name":"app-svc"}}

Technical Specifications & Engine Details

Technical specifications and engine details for YAML to NDJSON Converter
Specification Details
Supported Formats APPLICATION/X-YAML, TEXT/YAML, TEXT/PLAIN, .YAML, .YML → APPLICATION/X-NDJSON, APPLICATION/JSONL, TEXT/PLAIN, .NDJSON, .JSONL, .TXT
Execution Mode 100% Client-Side In-Browser (client)
Browser Requirements Modern browser with JavaScript enabled.
Performance Constraints Runs 100% client-side in browser memory. Performance bounded by local device RAM.
Maintained by Pragyan Pahadi

100% Client-Side Privacy Guarantee

Your files remain strictly on your local device. Zero data is transmitted to external servers.

Frequently Asked Questions

Is my YAML data secure and private?
Yes, 100%. All parsing and NDJSON generation run directly inside your browser using client-side JavaScript. No data is ever transmitted to an external server.
How are multi-document YAML streams handled?
Each document separated by '---' (or ended by '...') is parsed independently and output as a distinct JSON line in the resulting NDJSON stream.
What does the Array Unrolling option do?
When Unroll Array Items is enabled (default), a top-level YAML sequence of items (- item) is split so that each element becomes its own NDJSON line. When set to Preserve, the whole array is output on a single line.
Are comments and blank lines preserved?
YAML comments starting with # are stripped during parsing, and blank lines are ignored, ensuring your NDJSON output contains only clean, parseable JSON lines.
What is the maximum file size supported?
Because execution is 100% client-side in browser memory with zero network latency, you can convert large YAML files and streams containing tens of thousands of records smoothly.

Methodology

Rankings and recommendations here are never paid for.

Last updated .

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