YAML2JSON

YAML2JSON is a browser-based tool that converts YAML to JSON and back again instantly. You paste your YAML, the tool parses it, and you get formatted JSON output. Nothing you enter is transmitted or stored. The conversion runs entirely in your browser using the js-yaml library, which makes it safe for config files, CI/CD pipelines, Kubernetes manifests, and anything else you wouldn't want leaving your machine.

The converter supports full YAML 1.2 syntax including anchors, aliases, and merge keys. Multi-document YAML streams separated by triple dashes get converted to JSON arrays. If your YAML has a syntax error, the tool gives you a precise error message with line numbers instead of a generic parse failure. For developers who spend time debugging config files, that level of feedback matters.

Beyond the core converter, the site includes a YAML validator that checks syntax without converting. The output is pretty-printed JSON by default, so you can drop it straight into a config or paste it into an API request body. There's no setup, no account required for basic use, and no configuration templates to navigate. You paste, you convert, you copy.

The free tier covers unlimited conversions for anonymous users. If you need API access for automation, batch processing, or integration into your own tooling, paid plans start at 29 dollars a month for the Pro tier and 49 dollars for Business, which includes a thousand conversions monthly and team features. The API is the main unlock for paid users, the browser tool itself stays free.

Who it's for is developers, DevOps engineers, and anyone who works with configuration files regularly. If you've ever needed to transform a YAML config into JSON for an API, paste Kubernetes manifests into a tool that only accepts JSON, or just validate a config before deploying, this handles it without installing anything.

One limitation worth noting is that YAML comments don't survive the conversion. JSON has no comment syntax, so any inline notes in your YAML get stripped. That's a format constraint rather than a tool limitation, but it's worth knowing if you're using the output for documentation purposes.

The value proposition is simplicity. There are plenty of CLI tools and libraries that do this conversion, but having a trusted browser tool with instant feedback, precise error reporting, and no data transmission fills a practical gap. For occasional use, the free tier is enough. For automation, the API makes it scriptable.