The Three Contenders
JSON, YAML, and TOML are the most popular configuration formats. Each has clear strengths and weaknesses — choosing the right one depends on your use case.
JSON — The Universal Standard
- Pros: Universal parser support, strict syntax (fewer ambiguities), native to JavaScript, ideal for APIs
- Cons: No comments allowed, verbose (lots of quotes and braces), trailing commas illegal, not human-friendly for large configs
- Best for: API payloads, package.json, tsconfig, any machine-to-machine communication
YAML — The Human-Readable Choice
- Pros: Clean and readable, supports comments, multiline strings, anchors/aliases for reuse
- Cons: Indentation-sensitive (spaces only, no tabs), implicit typing can cause bugs ("yes" becomes boolean true), complex spec with surprising edge cases
- Best for: Docker Compose, Kubernetes manifests, CI/CD configs (GitHub Actions, GitLab CI), Ansible playbooks
TOML — The Simple Alternative
- Pros: Explicit typing, comments supported, clear table/array syntax, fewer gotchas than YAML
- Cons: Less widespread parser support, deeply nested structures become awkward, newer (less tooling)
- Best for: Rust (Cargo.toml), Python (pyproject.toml), simple project configs
Quick Decision Guide
- Need comments? → YAML or TOML
- API responses? → JSON (always)
- DevOps/infrastructure? → YAML (industry standard)
- Rust/Python project? → TOML
- Humans will edit it? → YAML or TOML
- Machines will generate it? → JSON
Convert Between Formats
Our YAML-JSON Converter lets you instantly switch between YAML and JSON formats. Paste in one format, get the other — all in your browser.