All Tools
Select a tool to validate your code. All tools support API access.
Data formats
Validate data formats — JSON, CSV, XML, YAML.
JSON Validator
Validate JSON syntax with precise error locations. Check for trailing commas, missing quotes, and malformed structures.
CSV Validator
Validate CSV structure, RFC 4180 quoting, and consistent column count per row.
XML Validator
Validate well-formed XML. Check unclosed tags, invalid attributes, syntax. Line and column errors.
YAML Validator
Validate YAML syntax. Check indentation, structure. Get line and column errors.
API & responses
Validate API responses, SOAP, webhooks, signatures, replay checks.
API Response Checker
Validate API response body as JSON. Paste raw HTTP response or JSON only; get line/column errors.
SOAP Response Validator
Validate SOAP response: well-formed XML and valid Envelope with Body or Fault. Paste raw HTTP or SOAP XML.
Webhook Payload Validator
Validate webhook payload: valid JSON and optional required top-level keys.
Signature Checker
Verify HMAC signature (SHA-256 or SHA-1) of a payload against a secret.
Replay Tester
Check if a timestamp is within an allowed time window (replay protection).
Markup & structure
HTML, schemas, data structure, config.
HTML Validator
Check HTML markup for syntax errors, unclosed tags, invalid nesting, and W3C compliance issues.
Schema.org Validator
Validate JSON-LD, Microdata, and RDFa structured data for SEO and rich search results.
XSD Schema Checker
Validate XML against an XSD schema. Paste XSD and XML; get line and column errors when the document does not conform.
Config Structure Checker
Validate JSON or YAML config: syntax and optional required top-level keys. Paste config, list required keys.
Config & env
CI config, .env files, secrets.
CI Config Linter
Lint CI config YAML: GitHub Actions and GitLab CI. Validate syntax and structure (on, jobs, steps, runs-on, script).
Env File Validator
Validate .env file syntax: KEY=value, comments (#), duplicate keys, invalid key names.
.env Syntax Checker
Check .env file line syntax: KEY=value, comments (#), invalid key names. Same API as Env File Validator.
Secrets Scanner
Scan text for potential secrets: passwords, API keys, tokens. Get line numbers and pattern names.
Regex & patterns
Regular expressions, glob patterns, pattern matching.
Regex Tester
Test regular expressions against text. See matches, capture groups, and flags (g, i, m, s).
Pattern Validator
Validate glob patterns and test paths. See which paths match (e.g. src/**/*.ts, *.json).
Match Debugger
Debug regex matches: see start index, end index, length, and matched text for each match.
Logs & errors
Log analysis, error patterns, log format validation.
Log File Analyzer
Analyze log files: count lines by level (ERROR, WARN, INFO, DEBUG, TRACE) and see sample lines.
Error Pattern Checker
Find log lines that match a pattern: plain text or regex. Get matching lines with line numbers.
Log Format Validator
Validate that each log line matches an expected format (regex). Paste logs, enter pattern, get invalid lines.
Encoding & hashing
Base64, checksums, hashes.
Base64 Encoder / Decoder
Encode text to Base64 and decode Base64 to text. Paste input, choose mode, get the result.
Checksum Checker
Compute MD5, SHA-1, or SHA-256 checksum of text. Optionally verify against an expected hash.
Hash Validator
Validate that a string is a valid hash format (hex length for MD5, SHA-1, SHA-256, etc.). Auto-detect or specify algorithm.
Date, time & IDs
Date, time, timestamps, UUIDs, IDs.
Date-Time Format Validator
Validate date-time strings (ISO 8601, RFC 2822). Get parsed result in ISO format.
ISO Compliance Checker
Check if a date-time string is strictly ISO 8601 compliant. Get violations and parsed result.
Timestamp Converter
Convert Unix timestamp (seconds or ms) to ISO date-time and vice versa.
UUID Generator & Validator
Generate UUID v4 and validate UUID format (version and variant).
ID Collision Checker
Paste a list of IDs (one per line); find duplicates and line numbers.
Format Checker
Validate a string against named formats: email, URL, IPv4, UUID, semver, etc.
SEO & crawlers
robots.txt, crawler access.
Error guides
Step-by-step guides for common validation errors:
FAQ
- What can I validate with these tools?
- You can validate JSON, HTML, CSV, XML, YAML, API responses, SOAP, webhooks, regex, config files, .env, logs, Base64, checksums, hashes, dates, timestamps, UUIDs, and more. All 33 tools are listed on the Browse Tools page and available via API.
- Is there an API? Can AI agents use it?
- Yes. GET /api/v1/status returns all endpoints and capabilities. Each validator has a POST endpoint (e.g. /api/v1/validate/json). Rate limit: 1 request per 10 seconds per IP without a key. The site is designed for both humans and AI: see /developers and /llms.txt for documentation and usage policy.
- Do I need to sign up?
- No. All tools are free to use in the browser without an account. API access is rate-limited without a key; no signup required for basic use.
- How do I fix a validation error?
- Each tool shows line and column when possible. We also have error guides: from a tool page or search, open a specific error (e.g. JSON trailing comma). Use «Try in validator» to prefill the broken example and fix it.
- Are short URLs supported?
- Yes. /json, /csv, /regex, /xml, /yaml, /html, /base64, and /robots redirect to the full tool pages for easy sharing.