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Free Online Validators - JSON, XML, YAML, Regex & More

Catch Errors Early

Invalid data causes real problems. Malformed JSON crashes applications. Broken XML fails integrations. Unsupported emojis show as boxes on some devices. Our validators help you catch these issues before they reach users or production systems.

For Developers

JSON validation — Check syntax, find missing brackets, validate against schemas. Essential for API development and config files.

XML and YAML — Verify structure, check well-formedness, catch common mistakes before deployment.

Regex testing — Build and test regular expressions with live matching. See what your pattern captures.

For Marketers & Writers

Emoji compatibility — Will your emoji render correctly in email clients? On older phones? Check before sending campaigns.

Content validation — Test that special characters and formatting will display correctly across platforms.

For DevOps

Config files — Validate Docker Compose, YAML configs, and deployment files before applying changes.

Invoices — Check e-invoice formats like PEPPOL, UBL, and XRechnung for compliance.

Instant Results

Paste data, see results immediately. Detailed error messages show exactly what's wrong and where. No upload delays — everything validates locally.

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