YAML to JSON Converter.

Convert YAML to JSON online — free and private

A YAML to JSON converter turns human-friendly YAML configuration into JSON that APIs, tools, and code consume directly. Paste your YAML above, press Convert to JSON, and the parser produces correctly typed JSON. Because it runs client-side, you can convert YAML to JSON online without uploading config files or secrets.

How to convert YAML to JSON in three steps

1. Paste your YAML into the input, or click “Load sample”.
2. Pick output formatting — pretty-printed or minified JSON.
3. Convert and export — copy the JSON or download it as data.json.

Handles the YAML you actually write

Real YAML has features simple parsers miss, so this one covers multi-document streams separated by ---, anchors and aliases (&name / *name), comment stripping, flow collections, and literal or folded block scalars. Type inference turns unquoted numbers and booleans into real JSON types while keeping quoted strings as text.

Anchors are the feature naive converters get wrong. YAML lets you define a block once and reuse it, which is common in docker-compose.yml and GitLab CI:

defaults: &defaults
  restart: always
  logging:
    driver: json-file

services:
  web:
    <<: *defaults
    image: nginx:1.27
  worker:
    <<: *defaults
    image: worker:2.1

JSON has no concept of a reference, so the anchor must be expanded — restart and logging are inlined into both web and worker. That is what this converter does; parsers that simply strip the & and * silently lose the shared values.

Convert YAML to JSON in Python, Node, or the terminal

Python (PyYAML) — always use safe_load, never load, which can execute arbitrary objects from untrusted YAML:

import json, yaml

with open("data.yaml") as f:
    data = yaml.safe_load(f)            # safe_load, not load

with open("data.json", "w") as f:
    json.dump(data, f, indent=2)

For a multi-document file, use safe_load_all:

docs = list(yaml.safe_load_all(open("manifests.yaml")))
json.dump(docs, open("manifests.json", "w"), indent=2)

Command line (yq) — the one-liner most CI jobs want:

yq -o=json eval data.yaml > data.json
# every document in a multi-doc file:
yq -o=json eval-all '[.]' manifests.yaml > manifests.json

Node.js (js-yaml):

import yaml from "js-yaml";
import { readFileSync } from "node:fs";

const data = yaml.load(readFileSync("data.yaml", "utf8"));
console.log(JSON.stringify(data, null, 2));

Common YAML to JSON problems (and fixes)

“Parse error and I cannot see why.” It is almost always a tab character. YAML bans tabs for indentation — spaces only. Turn on “show whitespace” in your editor and you will usually spot it immediately.

“My comments vanished.” Expected: JSON has no comment syntax, so there is nowhere to put them. Keep the YAML as your source of truth and treat the JSON as generated output.

“My multi-document file only converted the first manifest.” Documents separated by --- become a JSON array, one entry per document. If you only got the first, the tool you used ignored the stream — this one does not.

“NO turned into false.” The Norway problem: YAML 1.1 treats yes, no, on, and off as booleans. Quote the value ("NO") in your YAML to keep it a string.

“The JSON is hard to read.” Run it through the JSON formatter, explore it in the JSON viewer, or compare two configs with the JSON diff tool.

Why use this YAML to JSON tool?

It is fast, ad-free, and 100% private, with no file-size cap — which matters because the YAML you convert is usually a config file, and config files hold secrets, internal hostnames, and private registry credentials you should never paste into a server-side converter. Need the reverse? Use the JSON to YAML converter. Related: XML to JSON, CSV to JSON, JSON to TypeScript for typing a config, and JSON Schema generator to validate it. Learn more in our guide on how to convert YAML to JSON.