YAML Viewer

How to use YAML Viewer

1. Open YAML Viewer — it runs entirely in your browser with no setup.
2. Paste or type your input into the text area, or upload a file where supported.
3. Set any options you need. The result appears in the output panel — there is no upload step and no waiting on a server.
4. Review the output instantly; large inputs are handled locally without lag.
5. Copy the result to your clipboard or download it. Your data never leaves the page.

Why use YAML Viewer?

• 100% free with no limits, no sign-up and no watermarks.
• Private by design — your data are processed in your browser and never uploaded to a server.
• Fast and lightweight, with instant results even on a phone or a slow connection.
• Works everywhere — any modern browser on Windows, macOS, Linux, Android or iOS.
• Part of a full developer tools suite, so related yaml viewer tasks are one click away.

What people use YAML Viewer for

• Exploring a long Kubernetes, Compose or CI manifest as a collapsible tree.
• Checking how deeply a config is nested before editing it.
• Confirming that a value sits at the level you think it does.

YAML Viewer: limits and things worth knowing

• The tree shows what the parser produced, not what the text looks like — which is the fastest way to spot an indentation mistake that silently moved a key into the wrong parent.
• Anchors and aliases are resolved in the tree, so a value defined once and reused appears everywhere it applies.
• Type coercion is visible: a value shown as a boolean or a number when you meant a string is the classic YAML surprise, and quoting fixes it.
• YAML is a superset of JSON, so any valid JSON document is also valid YAML and can be pasted straight in.
• The Norway problem is real and this viewer shows it: unquoted no, yes, on and off parse as booleans in YAML 1.1, which is why the country code NO becomes false in a lot of configuration files. Quote them.
• Indentation must be spaces. Tabs are illegal in YAML at any level, and a tab pasted from an editor is the single most common cause of a parse error that looks like nothing is wrong.
• A leading zero makes a number an octal literal in YAML 1.1, so a zip code or a phone extension written as 0755 is read as 493. Quote anything numeric that is really a string.
• Anchors and aliases are expanded here so you can see what a merged document actually contains, which is usually the reason you opened it.
• The document is parsed in your browser. A Kubernetes secret or a CI configuration containing credentials can be inspected here without those values reaching a server.

Is it private and secure?

Your privacy is built in. YAML Viewer runs completely on your device, so whatever you enter stays in your browser and is never transmitted, logged or stored on any server.

Network activity: none. Nothing is sent and nothing is fetched. This tool makes no network request at all once the page has loaded — which is why it keeps working if your connection drops.

You do not have to take that on trust — our privacy proof page publishes the Content-Security-Policy that enforces it, lists every third party it permits, and shows how to verify the whole claim yourself.

Learn more

Working with JSON, XML and YAML: Format, Validate and Convert — Messy config or API response? Learn to pretty-print, validate and convert between JSON, XML, YAML and CSV in seconds.