YamlBox

Developer data tools · 19 converters

Convert YAML, JSON and data — without uploading anything

Free online developer tools — convert YAML to JSON, JSON to YAML, generate TypeScript, Go and SQL, and more. No signup, no uploads: everything runs locally in your browser.

Convert YAML to JSON Browse all 19 tools
Converters
19
Uploads
Zero
Signup required
Never
Works offline
Yes

Most used

YAML to JSON converter

Paste a config and see JSON immediately — 3 steps, no button, no upload. Multi-document YAML becomes an array; errors point at the exact line.

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Options

YAML input

Examples: Kubernetes manifest · App config · Multi-document — ⌘/Ctrl + Enter converts · drop a file to load it · processed locally

JSON output

Output is read-only. Use Copy, Download or Share to move it out.

Popular tools

All tools →
YAML to JSON Convert Kubernetes, Docker and CI configs to JSON with multi-document support. JSON to YAML Generate readable YAML from JSON with indentation and quoting controls. JSON to TypeScript Generate typed interfaces from JSON, with optional keys and unions inferred. JSON Formatter Pretty-print, minify and validate JSON with exact error locations. CSV to JSON Convert CSV/TSV exports to JSON arrays or JSON Lines. JWT Decoder Inspect JWT header, payload and expiry without leaving the browser.

Every tool, by category

19 focused utilities. Each one does a single job and does it properly — with real error messages, keyboard shortcuts and file input where it helps.

YAML tools

Work with YAML configs, Kubernetes manifests and CI files.

YAML to JSON Convert Kubernetes, Docker and CI configs to JSON with multi-document support. JSON to YAML Generate readable YAML from JSON with indentation and quoting controls.

JSON tools

Format, validate, explore and diff JSON documents.

JSON Formatter Pretty-print, minify and validate JSON with exact error locations. JSON Diff Compare two JSON files and list every change by path. JSON to JSON Schema Infer a validation-ready JSON Schema from any sample payload.

Code generators

Turn sample JSON into typed, ready-to-paste code.

JSON to TypeScript Generate typed interfaces from JSON, with optional keys and unions inferred. JSON to Go Generate Go structs with json tags and omitempty from JSON. JSON to SQL Generate CREATE TABLE and INSERT statements from JSON data.

Data converters

Move data between CSV, XML, Excel, subtitles and JSON.

CSV to JSON Convert CSV/TSV exports to JSON arrays or JSON Lines. JSON to CSV Convert JSON arrays into Excel-ready CSV or TSV files. XML to JSON Convert RSS, SOAP, sitemaps and config XML into predictable JSON. Excel to JSON Convert XLSX workbooks and spreadsheets to JSON, fully offline. SRT to VTT Convert SRT subtitles to WebVTT for HTML5 video players.

Web & encoding

URLs, Base64, JWTs, HTTP requests and timestamps.

JWT Decoder Inspect JWT header, payload and expiry without leaving the browser. Timestamp Converter Convert epoch seconds/millis to dates, or dates back to epoch. URL Encoder / Decoder Percent-encode URLs and decode query strings correctly. Base64 Encoder / Decoder Encode and decode Base64 with correct Unicode and URL-safe support. cURL to fetch Turn cURL commands into fetch, axios or node-fetch code. Markdown Table Generator Turn spreadsheets into aligned GitHub-flavoured Markdown tables.

Why the tools run in your browser

Your configs stay yours

Kubernetes secrets, JWTs, customer exports — the things you paste into tools are exactly the things you should not send to a stranger's server. Here, nothing is transmitted. The privacy claim is enforced by architecture, not by a policy page.

Instant, every keystroke

No request per conversion means no waiting, no rate limits and no “file too large” paywall. Conversion is local computation — a few milliseconds even for multi-megabyte documents.

Honest errors

When parsing fails you get the line, the column and a code excerpt — not “invalid input”. Debugging YAML indentation or a trailing JSON comma should take seconds, not a search engine query.

Guides

Learn the formats, not just the buttons

Practical write-ups: how YAML and JSON differ and when each wins, converting Kubernetes manifests safely, and generating TypeScript types that tell the truth about your API.

Read the guides

Frequently asked questions

Are these developer tools really free?

Yes — every tool is free with no account, no usage limit and no watermark. The site is funded without selling your data, which is possible precisely because nothing is processed on our servers.

Is my data uploaded anywhere?

No. Every converter is JavaScript running in your own browser tab. You can load a page, disconnect from the internet, and the tool keeps working. That also means we could not see your data even if we wanted to.

Which tool should I use for Kubernetes or CI configs?

YAML to JSON handles Kubernetes manifests, Helm values, GitHub Actions and GitLab CI files — including multi-document files, which become a JSON array rather than silently losing documents.

Do the tools work offline?

Yes, after the first load. The pages are static, and once the JavaScript is cached by your browser, conversions work without a network connection.

Can I share a conversion with a teammate?

Yes — the Share button copies a link with your input and settings embedded in the URL, so the other person opens exactly the same state. Because the input travels in the link, avoid sharing links that contain secrets.

More questions? See the full FAQ or contact us.

Blog

One guide for every tool

All 19 tool guides →