YAML to JSON Converter
Convert YAML configuration into valid JSON instantly.
Three steps, no reading required.
Paste your input
Drop text, code, or data into the input pane — from an API response, a file, anywhere.
See it process
The result updates instantly as you type.
Copy the result
Grab the output with Copy or Download, or fix the error shown if the input is invalid.
Try it with a sample.
name: DevUtilsNow features: - fast - private - free active: true
defaults: &defaults
image: nginx:1.27
restart: always
web:
<<: *defaults
ports: ["80:80"]
command: |
nginx -g 'daemon off;'
---
worker:
image: busybox
args: >-
sh -c
'echo hello'Convert first, find errors later
- Fails with a vague message on bad YAML
- Uploads your config files
- Flattens nested structures badly
Validates as it converts
- Reports the parse error so you can fix it first
- Expands anchors, aliases and merge keys; keeps | and > block text
- Your config never leaves the browser
Questions worth answering upfront.
No. Conversion happens entirely in your browser. Your YAML is never uploaded or stored.
Yes. If your YAML is malformed the tool reports the parse error so you can fix it before converting.
Yes. Nested maps and sequences are converted into the equivalent nested JSON objects and arrays.
Yes. Every tool on DevUtilsNow is free to use with no account required.
Not in general, but the reverse is true: YAML 1.2 is a superset of JSON, so any JSON document is also valid YAML. YAML adds indentation-based structure, comments and unquoted strings, which this tool turns into standard JSON.
Nested mappings and sequences, quoted and unquoted strings, numbers, booleans, null, inline [ ] and { } collections, comments, anchors and aliases, merge keys (<<), | and > block scalars, and multi-document files. Tags such as !!binary are not interpreted and complex keys are not supported, which rarely matters for config files.
Yes. An alias such as *defaults is replaced by the value anchored with &defaults, and a merge key (<<: *defaults) copies that mapping's keys into the current one, with keys you write yourself taking priority. JSON has no references, so the expanded values appear in full wherever they are used.
Each document separated by --- becomes one item of a JSON array, in order, so a multi-resource Kubernetes manifest turns into an array of objects. A file with a single document converts to that document on its own, not wrapped in an array. Anchors only apply within the document that defines them.
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Guides that pair with this tool
How to Convert YAML to JSON
How YAML maps to JSON, the indentation and type rules to know, and how to convert config from YAML to JSON reliably.
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