Configuration files, API responses, Docker, Kubernetes, CI/CD pipelines — they all speak JSON or YAML. Yet most courses skip them. This playground fixes that: every page has a live editor powered by a real JSON & YAML parser running in your browser. Type, watch it validate, convert one format to the other, and query nested data — no install, no internet.
Every web/mobile app talks to servers by sending and receiving JSON. Read an API response and you're reading JSON.
Docker Compose, Kubernetes, GitHub Actions, Ansible, GitLab CI — all configured in YAML files you edit by hand.
JSON and YAML are two ways of writing the same structure. Learn the shape once and both click.
Both formats describe the same three building blocks. Master these and everything else is syntax:
{
"user": "Aisha",
"roles": ["admin", "dev"],
"active": true
}user: Aisha roles: - admin - dev active: true
Same data — a key/value map, holding a list and a boolean. Only the punctuation differs. You'll convert between them live on page 7.
What structured data is, and where JSON & YAML show up in real life.
Objects, arrays, and the six value types — with a live editor for each.
The strict rules, and every common mistake — deliberately broken so you can fix them.
Reach into deep data with a.b[0].c — a live path explorer with a slider.
Keys, lists, indentation, comments — type YAML and watch the data appear.
Nested structures, multi-line strings, flow style, anchors & aliases.
A live two-way converter, plus the mental map linking every piece.
package.json, docker-compose.yml, a GitHub Action, a K8s manifest — decoded.
Paste any JSON or YAML: validate it, convert it, or query a path.
One-page reference plus puzzles the engine checks for you.
Saved in your browser — close the tab and come back where you left off.