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JSON.CO.UA
One place to format, validate, convert and debug your JSON — and check if Google will actually understand your structured data.
Runs entirely in your browser. Nothing is sent to any server. Free, forever.
🧹Format & Validate
Paste your JSON and it formats instantly, highlights syntax errors, flags duplicate keys, and shows you exactly which line is broken. No guessing, no cryptic error messages.
🏷️SEO Schema Validator
If your site uses structured data (<script type="application/ld+json">), this tool checks it against Google's requirements for Rich Results — star ratings, FAQ dropdowns, product prices in search. It scores your markup and tells you what's missing.
🔄Format Converter
Turn your JSON into CSV, YAML, XML or an interactive table in one click. Nested objects are flattened using dot-notation (brand.name, offers[0].price) so nothing gets lost in translation.
⇄JSON Diff
Paste two versions of a JSON document and see exactly what changed — added fields highlighted in green, removed fields in red, modified values shown side by side. Useful for comparing API responses or catching config drift.
Why validate your JSON?

Most JSON errors are silent. An unclosed bracket or a misplaced comma won't crash your app — it'll just fail quietly at runtime, return empty data to a user, or cause Google to ignore your structured data entirely.

Running your JSON through a validator takes about five seconds and catches the kind of mistakes that are genuinely embarrassing to find in production: a string where a number was expected, an array that should have been an object, a required Schema.org field that's simply missing.

If you're publishing structured data for SEO, the stakes are higher. Google won't grant rich results — those star ratings, FAQ boxes, and product details in search — if your JSON-LD has validation errors. A single typo in your @type or a missing name field can disqualify the entire block.

How to test any website's structured data
  1. 1
    Open the Fetch tab and paste the URL of the page you want to check. The tool fetches the page and extracts all <script type="application/ld+json"> blocks automatically.
  2. 2
    Review the raw JSON in the Format tab — look for syntax errors, missing fields, unexpected nesting.
  3. 3
    Send it to the SEO tab with one click and run the validator. You get a score from 0–100 and a breakdown of required, recommended and optional fields.
  4. 4
    Fix errors directly in the editor. The validator updates in real time as you type.
  5. 5
    Copy the corrected JSON-LD and replace the block on your site. Done — no account, no login, no upload.
This workflow takes a few minutes per page and tells you clearly whether your structured data is eligible for rich results — without needing access to Google Search Console or any external API.
What a good SEO score actually gets you

Structured data doesn't guarantee rich results, but missing or broken structured data guarantees you won't get them. A score of 80+ in the SEO tab means you've covered all required fields and most recommended ones — that's the range where most Schema.org types become eligible.

For content teams: this is one of the few SEO improvements that's both measurable and within your direct control. You don't need to wait for domain authority to grow or backlinks to accumulate — add the JSON-LD, validate it here, deploy it, and Google typically picks it up within a few days.

Product FAQPage Article LocalBusiness BreadcrumbList HowTo Recipe Event VideoObject JobPosting Review Course
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Samples:
INPUT
Waiting for input
OUTPUTFORMATTED
{}
No output yet
Start typing to see realtime output
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Live Validation
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0 chars| 0 lines| —| Ctrl+Enter: Format · Esc: Close dialogs
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VERSION A — Original
VERSION B — Modified
DIFF RESULT
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Paste JSON in both panels — diff updates in realtime
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TO:
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INPUT (JSON)
OUTPUT (CSV)
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Select formats and start typing
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Quick Tests:

↓ CORS Handled

JSON.CO.UA tries a direct request first, then falls back to the allorigins.win proxy automatically.

↓
Enter a URL and fetch
// Response appears here
Accepts: raw JSON or full HTML page with ld+json
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ld+json / HTML INPUT
Paste ld+json or full HTML
Paste raw JSON · <script type="application/ld+json"> · or full HTML — all work
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SEO Validation
Paste ld+json or full HTML above
Auto-validates on every keystroke
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json.co.ua — Knowledge Base

JSON & Structured Data
Questions Answered

The most-searched questions about JSON formatting, conversion, validation and schema.org structured data — written for developers and SEO professionals.

⌕
JSON (JavaScript Object Notation) is a lightweight text-based data interchange format using key-value pairs and arrays. It is language-agnostic, compact, and natively supported in every modern programming language. REST APIs, configuration files, NoSQL databases like MongoDB, and front-end/back-end services all use JSON as their universal exchange format.
Paste your JSON into JSON.CO.UA — it auto-formats in realtime as you type. Choose 2 spaces, 4 spaces, or tabs. The output is syntax-highlighted for easy reading. Press Ctrl+Enter to format instantly.

Programmatically: JSON.stringify(data, null, 2) in JavaScript, json.dumps(data, indent=2) in Python.
JSON supports 6 data types: string ("text"), number (42, 3.14), boolean (true/false), null (null), array ([]), and object ({}). Unlike JavaScript, JSON does not support undefined, functions, or comments.
Your JSON must be an array of objects with consistent keys. Open the Convert tab, select JSON → CSV, paste your data and the result appears in realtime. Nested objects are serialised as compact JSON strings — no data is lost. The resulting CSV opens directly in Microsoft Excel or Google Sheets.
JSON uses strict syntax with braces and quoted keys — fast to parse, unambiguous. YAML uses indentation — more human-readable but sensitive to whitespace. JSON is preferred for APIs and data storage. YAML is preferred for configuration files (Kubernetes, Docker Compose, GitHub Actions). JSON.CO.UA converts between them instantly in the Convert tab.
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JSON is more concise — smaller payloads, faster parsing, native browser support via JSON.parse(). XML supports attributes, namespaces, and comments. JSON dominates modern REST APIs. XML remains important in document formats (SVG, DOCX, RSS) and legacy enterprise systems (SOAP, EDI). Use JSON.CO.UA's Convert tab to switch between them instantly.
1. Single object instead of array — wrap in [].
2. Nested objects — JSON.CO.UA serialises them as compact JSON strings automatically.
3. Inconsistent keys — missing values become empty CSV cells.
4. Values with commas — JSON.CO.UA auto-quotes them correctly.
5. Non-UTF-8 encoding — always save as UTF-8 to preserve non-ASCII characters.
JSON.CO.UA shows errors in realtime as you type — the status badge turns red with an exact error message. Click Repair to auto-fix common issues: trailing commas, unquoted keys, and single-quoted strings. Most common mistakes: missing comma between properties, trailing comma before }, and using // comments (not allowed in standard JSON).
Use the Diff tab. Paste Version A and B — the comparison updates in realtime. JSON.CO.UA uses the LCS (Longest Common Subsequence) algorithm, the same as git diff: green for added lines, red for removed, grey for unchanged. Enable Sort keys to ignore key-ordering differences.
728 × 90 — Google AdSense
JSON-LD is a W3C standard for embedding schema.org structured data inside a <script type="application/ld+json"> tag. Google uses it to generate rich results — star ratings, FAQ dropdowns, recipe cards, event listings — increasing click-through rates by 20–30%. It is Google's officially recommended format and requires no changes to your visible HTML.
Schema.org is a shared vocabulary created by Google, Microsoft, Yahoo, and Yandex. For rich results use: Article for blog posts, Product + Offer for e-commerce, LocalBusiness for service businesses, FAQPage, Event, Recipe, HowTo, JobPosting, Course, VideoObject. JSON.CO.UA supports 35+ types with templates and full validation.
JSON.CO.UA's SEO tab auto-validates as you type. Paste raw JSON, a <script type="application/ld+json"> block, or a full HTML page — all ld+json blocks are extracted automatically. For official testing also use Google Rich Results Test and validator.schema.org.
Always: @context: "https://schema.org" and correct @type.
Article: headline, author, datePublished, image, publisher.
Product: name, image, offers (price + currency), aggregateRating for star ratings.
FAQPage: mainEntity → Question + acceptedAnswer.
LocalBusiness: name, address, telephone, openingHours.
Images ≥ 1200×628px. Dates in ISO 8601. All URLs absolute with https://.
No questions match your search.

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