YAML Validator

Validate YAML configs with exact line numbers, reformat them cleanly, and see the JSON equivalent side by side - all locally in your browser.

The JSON view of your YAML appears here.

What is YAML?

YAML ("YAML Ain't Markup Language") is a human-friendly data format used everywhere in modern software: GitHub Actions and GitLab CI pipelines, Docker Compose files, Kubernetes manifests, Ansible playbooks, and app configuration like this site's own deploy files. It uses indentation instead of braces, which makes it pleasant to read but easy to break - one wrong space can change the meaning of the whole file.

Why validate before you commit?

A broken YAML file usually fails at the worst moment - when your CI pipeline runs or your server tries to start. Validating locally catches indentation slips, missing colons, unbalanced quotes, duplicate keys, and tabs (which YAML forbids) before they reach production. This tool parses your file exactly like a real YAML parser would and reports the precise line and column of any problem.

Common YAML mistakes

The most frequent errors are mixing tabs with spaces, inconsistent indentation between sibling keys, forgetting a space after a colon (key:value instead of key: value), leaving a quote unclosed, and writing an unquoted value that starts with a special character like * or &. Nepal-specific tip: if your values contain Devanagari text, always save the file as UTF-8 so characters like काठमाडौं survive the round trip.

Formatting and multi-document files

The Format button rewrites your file with clean two-space indentation and consistent quoting without changing any data. YAML also supports several documents in one file separated by --- lines; this validator parses every document and tells you how many it found, then reformats each one.

Converting YAML to JSON

JSON is a strict subset of YAML's data model, so every valid YAML file converts to equivalent JSON. The right-hand panel shows that conversion live - handy when a tool accepts only JSON but your source of truth is YAML, or when you want to diff two configs programmatically.

Privacy and security

Parsing happens entirely in your browser with JavaScript. Your configuration - including any secrets, tokens, or server addresses it may contain - is never uploaded, logged, or stored on any server. Refresh the page and it is gone.

100%

Free, always

Sign-up needed

Unlimited

Uses

Private

Runs in browser

Offline

Works without net

Made for YAML Validator in Nepal

Developers and DevOps checking YAML configs before deploying.

DevOps engineers

Lint Kubernetes and CI configs in Kathmandu.

CS students

Learn infrastructure-as-code safely.

Freelancers

Fix client YAML before delivery.

Sysadmins

Verify Ansible playbooks offline.

Startups

Catch config errors before deploy.

Researchers

Validate pipeline definition files.

What is a YAML validator, and how does this free Nepal tool work?

A YAML validator parses your YAML and reports syntax errors with line numbers so configs are safe to deploy. Scolar’s tool runs in your browser: paste or upload YAML, validate, and read any issues. No sign-up, no watermark, nothing uploaded.

Why it is free, with no sign-up and unlimited use

Parsing happens on your device, so your config stays local and no account is needed. That keeps it 100% free with unlimited validations and no watermark.

How to use this tool, step by step

Paste or upload your YAML configuration.
Validate it; errors show with line numbers.
Fix and re-check; the file never leaves your device.

YAML in Nepal

DevOps engineers in Kathmandu linting Kubernetes and CI configs, students learning infrastructure-as-code, and freelancers fixing client YAML all validate constantly. Offline checking keeps possibly secret configs off third-party sites.

“A Nepali DevOps engineer should not pay for an app just to validate YAML. Paste, check, fix — free.”

YAML checks done free in Nepal

I validate K8s YAML here — free, no signup.

YR Yubaraj Rai DevOps engineer

Learned YAML indentation the easy way. Free.

SP Sarala Poudel CS student

Client configs checked locally. Private, no cost.

BG Bikram GC Freelancer

How it works

Paste or type your YAML on the left - it validates as you type with live status.

If there is an error, jump to the reported line and column; otherwise press Format to tidy indentation.

Read the JSON equivalent on the right, then Copy or download the result as a .yaml file.

Why use this tool?

Errors point to the exact line and column where parsing failed, not just a vague message.
Multi-document files (separated by ---) are validated and reformatted as a whole.
Everything runs locally in your browser - secrets in your config never leave your device.

Frequently asked questions

Is my YAML file uploaded to a server?

No. Validation, formatting, and JSON conversion all run locally in your browser using JavaScript. Nothing you paste ever leaves your device.

Why does YAML complain about tabs?

The YAML specification forbids tab characters for indentation because they render differently across editors. Replace tabs with spaces - two spaces per level is the convention.

Can it validate multi-document YAML?

Yes. Files containing several documents separated by --- lines are fully supported, and the status bar reports how many documents were found.

Does formatting change my data?

No. Formatting only normalises indentation, spacing, and line width. Keys, values, and their order stay exactly the same.

How do I fix "bad indentation" errors?

Make sure sibling keys sit at exactly the same depth and nested content is indented further than its parent. The error message shows the exact line and column where parsing failed.

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