About JSONYard

JSONYard is a free, browser-only collection of JSON tools — format, validate, repair, query with JSONPath, validate against schemas, diff, and convert to/from CSV, XML, and YAML.

Why another one?

There are plenty of JSON formatters online. Most of them do the same three things — pretty-print, minify, validate — and surround the tool with banner ads that load before the editor does. We wanted something faster, with the features developers actually use after the basics: tolerant repair for broken JSON, off-thread parsing for large files, JSONPath, structural diff, and schema validation, all in one place. And the unbreakable rule: your data never leaves your browser.

Maintainer

Sam Okafor — backend engineer, independent maintainer of JSONYard.

Sam has been writing software professionally since 2013, mostly in the gap between data pipelines and APIs: Python, Go, a long stretch of Node, and a too-long stretch of XSLT before that. JSONYard started as a small private repo of "things I'd already typed into a REPL three times" — a tolerant parser for the JSON-with-comments your colleagues keep checking in; a JSONPath engine that doesn't silently drop filter expressions; a CSV converter that knows the difference between an unquoted number and a phone number that happens to start with a digit. After fielding the same questions on internal Slack for years ("why is my big ID off by one when it round-trips through JSON?"), publishing the tools and the answers in one place felt overdue.

The bugs that motivated specific features are still in the code as comments — search the repo for // motivating-case: if you want the war stories.

Find Sam on: GitHub · LinkedIn · Mastodon

The maintainer reads every message that comes through the contact page. Real human, real reply (within a few days, usually faster on weekends).

How this site is built

The whole site is vanilla HTML, CSS custom properties, and ES modules. There is no framework, no bundler, no build step, no node_modules, and no third-party runtime dependencies — every byte the browser executes is in the assets/ tree of the public repo. The JSON parser, the tolerant repair pass, the JSONPath engine, the JSON Schema validator, the structural diff, the CSV/XML/YAML converters — all hand-written. That's an intentional constraint: when something behaves weirdly we can fix it the same afternoon, and there is no supply-chain risk from a dependency we never audited.

There is no analytics, no fingerprinting, and no third-party script of any kind by default. When advertising is eventually enabled, the only third party is Google AdSense, gated behind a Google-certified consent banner — see the Privacy Policy.

What we promise

  • Client-side only. Parsing, formatting, validation, conversion — all happen in your browser. Verify in your devtools' Network tab.
  • No tracking of content. We do not look at, log, or analyze the JSON you paste.
  • No dark patterns. No autoplay anything, no fake "limited" buttons, no upsells to a premium plan that isn't real.
  • Ads when they appear will be standard banner ads, clearly separated from the tool, and gated behind a cookie-consent banner for users in regions that require one.

Keyboard shortcuts

  • Ctrl/⌘+Enter — Format / Beautify
  • Ctrl/⌘+M — Minify
  • Tab in editor — insert two spaces

Editorial standards

Blog posts on JSONYard are written by the maintainer from direct experience with the bugs and edge cases described. We do not republish AI-generated explainers, and we do not accept paid placements or sponsored posts. When a post recommends a third-party tool, it's because we use it.

Last reviewed: 2026-06-13.