Data Validators

Validate TOML configuration files for syntax errors, duplicate keys, invalid values, and specification compliance with detailed error messages - Free online TOML validator

Validate TOON (Token-Oriented Object Notation) files for syntax errors, array count mismatches, invalid escape sequences, and specification compliance - Free online TOON validator

Validate YAML files for syntax errors, indentation issues, duplicate keys, anchor/alias validation, and YAML 1.2 specification compliance - Free online YAML validator

Validate JSON files for syntax errors, duplicate keys, trailing commas, invalid escape sequences, and RFC 8259 compliance - Free online JSON validator

Validate XML files for well-formedness errors, mismatched tags, duplicate attributes, invalid entity references, and XML specification compliance - Free online XML validator

Validate INI configuration files for syntax errors, duplicate sections, duplicate keys, invalid section headers, and INI format compliance - Free online INI validator

Validate HOCON configuration files for syntax errors, mismatched braces, invalid substitutions, duplicate keys, and HOCON specification compliance - Free online HOCON validator

Validate CSV files for column count inconsistencies, quoting errors, unterminated fields, mixed line endings, and RFC 4180 compliance - Free online CSV validator

Validate .env dotenv files for invalid key names, duplicate keys, quoting errors, escape sequence issues, and naming convention compliance - Free online .env validator

Validate HTML files for unclosed tags, invalid nesting, missing attributes, deprecated elements, and HTML5 compliance - Free online HTML validator

Validate CSS stylesheets for syntax errors, unclosed blocks, invalid properties, malformed selectors, and structural issues - Free online CSS validator

Validate RSS 2.0 and Atom 1.0 feeds for syntax errors, missing required elements, invalid dates, and structural issues - Free online feed validator

Validate robots.txt files for syntax errors, invalid directives, path issues, sitemap URLs, crawl-delay values, and structural best practices - Free online robots.txt validator

Validate sitemap XML files and sitemap index files for XML errors, missing elements, invalid URLs, date format issues, and protocol compliance - Free online sitemap validator

Validate Open Graph meta tags for required properties, URL formats, image dimensions, Twitter Cards, type-specific properties, and social sharing best practices - Free online OG validator

Validate GraphQL schema definitions for type errors, field references, naming conventions, directives, enums, unions, interfaces, and structural issues - Free online GraphQL validator

Validate Protocol Buffer (.proto) schema files for message definitions, field numbers, enum values, service definitions, naming conventions, and proto2/proto3 compliance - Free online Protobuf validator

Validate and lint Dockerfiles for syntax errors, best-practice violations, security issues, deprecated instructions, multi-stage build problems, and common anti-patterns - Free online Dockerfile linter

Validate docker-compose.yml files for service definitions, port conflicts, volume/network references, dependency ordering, environment variables, and best-practice violations - Free online Docker Compose validator

Validate Nginx configuration files for syntax errors, SSL/TLS issues, proxy misconfigurations, security vulnerabilities, and best-practice violations - Free online Nginx validator

Validate Apache httpd.conf and .htaccess files for syntax errors, container mismatches, SSL/TLS issues, deprecated directives, security vulnerabilities, and best-practice violations - Free online Apache validator

Validate Terraform HCL configuration files for syntax errors, block structure, missing attributes, duplicates, security issues, and best-practice violations - Free online Terraform validator

Validate Kubernetes YAML manifests for syntax errors, missing fields, apiVersion/kind issues, container configuration, resource limits, and best-practice violations - Free online K8s validator

Validate GitHub Actions workflow YAML for syntax errors, trigger events, job configuration, step validation, circular dependencies, cron schedules, and permissions - Free online GHA validator

Validate Ansible playbook YAML for syntax errors, play structure, task modules, handler references, privilege escalation, Jinja2 expressions, deprecated modules, and best practices - Free online Ansible validator

Validate and lint Markdown files for heading structure, link syntax, image alt text, code blocks, list formatting, table alignment, emphasis markers, and best practices - Free online Markdown linter

Validate ads.txt files for format errors, invalid domains, account types (DIRECT/RESELLER), duplicate entries, TAG-ID certification authority IDs, and IAB specification compliance - Free online ads.txt validator

Validate JSON-LD structured data for Schema.org type errors, missing required properties, invalid URLs, date format issues, @graph arrays, and Google rich results eligibility - Free online structured data validator

Validate JSON-LD structured data for JSON syntax errors, Schema.org type validation, missing properties, @graph support, and Google rich results eligibility - Free online JSON-LD validator

Validate semantic version strings against Semver 2.0.0 specification for correct MAJOR.MINOR.PATCH format, pre-release identifiers, build metadata, leading zeros, and range expressions - Free online semver validator

Validate UUID and GUID strings against RFC 4122 and RFC 9562 for correct 8-4-4-4-12 hex format, version nibble, variant bits, nil/max UUID detection, and multiple input formats - Free online UUID validator