What is a YAML to JSON Converter?
Hand a YAML config to a tool that only eats JSON and you have a problem; this converter solves it in the browser without touching your data on a server.
YAML is what humans write — Kubernetes manifests, GitHub Actions, CircleCI configs. JSON is what APIs and JavaScript runtimes consume. Converting between the two lets you keep the source of truth in whichever format your workflow prefers.
Nested structures, anchors, aliases, and multi-line strings are all resolved faithfully. You can download the JSON file directly or copy it to the clipboard.
How to Use Our YAML to JSON Converter
- Paste your YAML data into the input editor or use the sample data button
- Configure your JSON output settings (indentation, formatting, etc.)
- Preview the JSON output in real-time
- Download the converted JSON file or copy to clipboard
Examples
YAML types map cleanly to JSON equivalents: strings, numbers, booleans, null, sequences, and maps all survive the round trip. Anchors and aliases are expanded inline since JSON has no reference semantics.
Example 1: Kubernetes Deployment fragment
A slice of a Deployment manifest converts into the equivalent JSON tree, with integers and booleans typed correctly instead of quoted.
Input
apiVersion: apps/v1
kind: Deployment
metadata:
name: web
spec:
replicas: 3
template:
spec:
containers:
- name: app
image: nginx:1.25
ports:
- containerPort: 80Output
{
"apiVersion": "apps/v1",
"kind": "Deployment",
"metadata": { "name": "web" },
"spec": {
"replicas": 3,
"template": {
"spec": {
"containers": [
{
"name": "app",
"image": "nginx:1.25",
"ports": [{ "containerPort": 80 }]
}
]
}
}
}
}Example 2: Multi-document YAML as a JSON array
Documents separated by --- turn into a JSON array where each entry is one parsed document.
Input
---
kind: Service
name: web
port: 80
---
kind: ConfigMap
name: web-config
data:
log_level: info
Output
[
{ "kind": "Service", "name": "web", "port": 80 },
{
"kind": "ConfigMap",
"name": "web-config",
"data": { "log_level": "info" }
}
]YAML specification reference
Quick reference from YAML 1.2. The converter enforces these rules on input; anything outside them is rejected or normalized.
| Element | Meaning | Example |
|---|
| Mapping | Block or flow key/value pairs | name: alice |
| Sequence | Ordered list with `- ` or flow `[...]` | - apple
- banana |
| Scalar | Plain, single-quoted, double-quoted, literal `|`, folded `>` | "hello\n" |
| Anchor / alias | & defines, * references; enables DRY configs | &base
*base |
| Tag | Explicit type: !!int, !!str, !!binary … | !!int "42" |
Common invalid forms
name:alice // missing space after colon
- item
-indented // inconsistent indent
flag: yes
value: 1 // tab used for indent (YAML forbids tabs)
Key Features
Deeply nested objects and arrays convert faithfully, anchors (&) and aliases (*) expand inline since JSON has no reference semantics, and YAML types map cleanly to their JSON equivalents (strings, numbers, booleans, null).
- Real-time preview as you edit
- One-click file download or clipboard copy
Why Use Our YAML to JSON Converter?
The converter stays minimal on purpose. For developers, SREs, and config managers, it offers:
- Privacy-focused:Your data never leaves your browser - we don't store any of your data on our servers
- Format preservation: Maintain data structure and hierarchy
- Nested support: Handle complex YAML structures with nested objects and arrays
- Real-time preview: See your JSON output before downloading
- No installation needed: Access our tool from any browser without downloading or installing anything
Common Use Cases
Converting YAML to JSON is useful in various scenarios:
- API Development: Convert YAML configuration to JSON for API requests
- Configuration Management: Transform YAML configs to JSON for web applications
- Data Integration: Bridge YAML and JSON data formats
- Development Workflow: Convert YAML to JSON for JavaScript applications
- System Configuration: Transform YAML settings to JSON for system tools
Frequently Asked Questions
Q: Does the converter preserve YAML comments in the JSON output?
No. YAML comments (lines starting with #) are not included in the JSON output because JSON does not support comments as part of its specification. Only data values, keys, and structural information are carried over to the resulting JSON.
Q: How are YAML anchors and aliases handled?
YAML anchors (&) and aliases (*) are fully resolved during conversion. The resulting JSON contains the expanded values, so all referenced data is duplicated inline as JSON does not support reference semantics.
Q: Are YAML multi-line strings preserved in JSON?
Yes, YAML multi-line strings (using | or > syntax) are converted to JSON strings with appropriate newline characters. The literal and folded block styles are both supported and correctly transformed.
Q: Does the converter support YAML multi-document files?
The converter processes the first YAML document in a multi-document file (separated by ---). For multiple documents, you can convert each one separately to get individual JSON outputs.
Q: How are YAML data types mapped to JSON?
YAML types are mapped to their JSON equivalents: strings become JSON strings, numbers become JSON numbers, booleans become true/false, null values become JSON null, and sequences become JSON arrays.