Semver Validator
Validate semantic version strings online for free. Our validator checks against the Semver 2.0.0 specification for correct MAJOR.MINOR.PATCH format, pre-release identifiers, build metadata, leading zeros, range expressions, duplicates, and sort order. Supports batch validation with one version per line.
Why Use Our Semver Validator?
Instant Validation
Our tool to validate semver analyzes your content instantly in your browser. Validate Semver files of any size with zero wait time - get detailed error reports with line numbers in milliseconds.
Secure & Private Processing
Your data never leaves your browser when you use our semver validator online tool. Everything is processed locally using JavaScript, ensuring complete privacy and security for sensitive configuration data.
No File Size Limits
Validate large Semver files without restrictions. Our free Semver Validator handles any size input - from small configs to massive files with thousands of entries.
100% Free Forever
Use our Semver Validator completely free with no limitations. No signup required, no hidden fees, no premium tiers - just unlimited, free validation whenever you need it. The best free semver validator online available.
Common Use Cases for Semver Validator
Package Management
Validate version strings in package.json, Cargo.toml, setup.py, or any package manager configuration. Ensure correct MAJOR.MINOR.PATCH format and valid pre-release identifiers before publishing.
Release Management
Verify release version tags follow Semver 2.0.0 before creating Git tags or GitHub releases. Catch leading zeros, invalid pre-release labels, and formatting issues early.
API Versioning
Validate API version strings to ensure they communicate backward compatibility correctly. Major version increments signal breaking changes, minor versions add features, and patches fix bugs.
Dependency Auditing
Validate version constraints and ranges used in dependency files. Detect npm-style range operators (^, ~, >=) and ensure they reference properly formatted base versions.
Changelog Verification
Validate version numbers listed in changelogs and release notes. Check for duplicates, proper ordering, and format consistency across your project's version history.
CI/CD Version Gates
Validate version strings in CI/CD pipelines before building, tagging, or deploying. Ensure automated versioning tools produce spec-compliant version numbers.
Understanding Semver Validation
What is Semver Validation?
Semver validation is the process of checking Semantic Versioning 2.0.0 files (.txt) for syntax errors, structural issues, invalid values, duplicate keys, and specification compliance - helping you catch problems before deployment. Semver is widely used for communicating meaningful version information about software changes through a structured MAJOR.MINOR.PATCH format where incrementing each component signals breaking changes, new features, or bug fixes respectively. Our free semver validator online tool checks your content instantly in your browser. Whether you need to validate semver for npm package versioning, library releases, API versioning, Git tag validation, changelog version checking, dependency constraint auditing, CI/CD pipeline version gates, and release management, our tool finds errors accurately and privately.
How Our semver validator Works
- Input Your Semver Content: Paste your Semver content directly into the text area or upload a
.txtfile from your device. Our semver validator online tool accepts any Semver input. - Instant Browser-Based Validation: Click the "Validate Semver" button. Our tool analyzes your content entirely in your browser - no data is sent to any server, ensuring complete privacy.
- Review Detailed Error Reports: View a comprehensive list of errors with line numbers, descriptions, and severity levels. Fix issues with pinpoint accuracy using our clear error messages.
What Gets Validated
- Syntax Correctness: Checks for proper syntax including balanced brackets, correct string quoting, valid escape sequences, and proper key-value pair formatting.
- Data Types: Validates integers, floats, booleans, strings, datetimes, arrays, and inline tables conform to the Semver specification.
- Structural Integrity: Detects duplicate keys, conflicting table definitions, invalid table headers, and malformed sections.
- Line-by-Line Reporting: Every error includes its exact line number and a clear description, making it easy to find and fix issues in your Semver files.
Privacy, Security & Availability
Our semver validator online runs 100% client-side in your browser using JavaScript - your Semver content is never uploaded to any server, stored in a database, or transmitted anywhere. This makes it safe to validate sensitive configuration files, API keys, and internal infrastructure definitions. The tool is completely free with no signup, no usage limits, and no premium tier. Use it as many times as you need for any project - personal, commercial, or enterprise - at no cost.
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Frequently Asked Questions - semver validator
A semver validator is a tool that checks version strings against the Semantic Versioning 2.0.0 specification. Our semver validator online tool verifies MAJOR.MINOR.PATCH format, pre-release identifiers, build metadata, leading zeros, and common formatting mistakes entirely in your browser.
Our validator detects missing version components (MINOR/PATCH), leading zeros in numeric identifiers, invalid pre-release label characters, empty dot-separated identifiers, v-prefix usage, invalid build metadata, npm-style range operators, wildcard versions, duplicate versions, and unsorted version lists.
Absolutely! Your data is completely secure. All validation happens directly in your browser using JavaScript so no data is ever uploaded to any server. Your version strings never leave your device.
The correct format is MAJOR.MINOR.PATCH (e.g., 1.2.3). Optionally, a pre-release identifier can be appended with a hyphen (1.2.3-alpha.1) and build metadata with a plus sign (1.2.3+build.456). All three numeric components are required and must not have leading zeros.
Yes! Enter one version per line and the validator will check each one. It also detects duplicates and checks if versions are in sorted order. Lines starting with # or // are treated as comments and skipped.
Yes! The validator identifies npm/node-semver range syntax like ^1.2.3, ~1.0.0, >=2.0.0, 1.x, and hyphen ranges (1.0.0 - 2.0.0). These are flagged as warnings since they are valid for package managers but not part of Semver 2.0.0.
Yes, our semver validator is 100% free with no hidden costs or limitations. There is no signup required, no premium tier, no usage limits, and no file size restrictions. Use it unlimited times for any project.
Versions with major version 0 (0.y.z) indicate initial development where the public API is not considered stable per the Semver 2.0.0 specification. Anything may change at any time. This is informational - not an error.