Alternatives to Validator.nu

Discover websites similar to Validator.nu based on shared categories, topics, and features.

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jshint.com favicon

Instantly check JavaScript code for errors

59%

JSHint helps you find errors and potential issues in your JavaScript code, making it easier to write clean, reliable, and maintainable programs.

validator.w3.org favicon

Validate your website's HTML for standards compliance

57%

Check your website’s HTML or XHTML for errors and standards compliance with this easy-to-use markup validation service from the World Wide Web Consortium.

stylelint.io favicon

Catch CSS errors and enforce style rules

57%

Stylelint is a CSS linter that helps you find errors and enforce style rules in your stylesheets, making your code cleaner and more consistent.

jslint.com favicon

Analyze JavaScript code instantly in your browser

57%

Check your JavaScript code for errors and quality issues right in your browser—no downloads or uploads required.

nunit.org favicon

Test .NET code easily with NUnit's open framework

57%

NUnit offers a free, open-source framework for unit testing .NET code, helping developers write and run tests to ensure their projects work as intended.

biomejs.dev favicon

Format and lint code instantly for web projects

57%

Biome is a fast toolchain for web projects that formats and lints JavaScript, TypeScript, CSS, and more to save developers time and boost code quality.

tracy.nette.org favicon

Debug PHP code with clear error visualization

57%

Tracy is a PHP debugging tool that helps developers visualize errors, log issues, and inspect variables for easier, more effective troubleshooting.

codacy.com favicon

Automate code quality and security checks

55%

Codacy helps developers improve code quality and security by automating checks, enforcing standards, and integrating seamlessly into your workflow.

sonarsource.com favicon

Automate code quality and security checks

55%

SonarQube helps you automatically review code for quality and security issues, offering insights to help developers write clean, secure code faster.

tiobe.com favicon

Assess and improve your software code quality

55%

TIOBE helps you measure and improve software code quality with tools, assessments, and insights for better maintainability and project outcomes.

eslint.org favicon

Automatically spot and fix JavaScript code issues

55%

ESLint helps you find and fix problems in your JavaScript code with easy-to-use linting tools that improve code quality and consistency.

scrutinizer-ci.com favicon

Automate code reviews and boost software quality

55%

Scrutinizer helps you manage software quality with automated code analysis, continuous integration, and smart tools for better code reviews.

html-tidy.org favicon

Easily clean and fix your HTML code

55%

HTML Tidy helps you clean up and fix HTML code, making your web pages more readable and standards-compliant. Free and open source for all users.

codecov.io favicon

Track and improve your code coverage easily

55%

Codecov helps developers track code coverage, spot flaky tests, and improve code quality with insightful reports and easy integration into CI workflows.

pvs-studio.com favicon

Catch code errors and security flaws early

55%

PVS-Studio helps you find bugs and security issues in C, C++, C#, and Java code with advanced static analysis tools for multiple platforms.

valgrind.org favicon

Find memory bugs and profile your code easily

55%

Valgrind offers a suite of tools to help you detect memory and threading bugs, profile your programs, and improve code quality for better software reliability.

webhint.io favicon

Spot website issues and improve best practices

55%

webhint checks your website for best practices, accessibility, speed, and compatibility issues, helping you easily spot and fix common web development errors.

xdebug.org favicon

Debug and profile your PHP code easily

46%

Xdebug is a PHP extension that helps you debug, profile, and improve your PHP code for a smoother development experience.

parasoft.com favicon

Automate testing for better, faster software releases

44%

Parasoft offers AI-powered automated testing tools to help teams improve software quality, ensure compliance, and deliver secure code faster.

linter.structured-data.org favicon

Instantly check your page's structured data

39%

Check your web page's structured data by entering a URL, uploading a file, or pasting markup. Instantly see what schema is detected and how it's structured.

More Validator.nu Alternatives

mypy-lang.org favicon

Check Python code with optional static typing

57%

Mypy is a tool for Python that lets you add optional static typing to your code, helping you catch errors early and write more reliable programs.

findbugs.sourceforge.net favicon

Detect bugs in Java code with static analysis

55%

FindBugs is a free tool for analyzing Java programs and detecting bugs using static code analysis, helping developers improve code quality and security.

urlencoder.org favicon

Instantly encode or decode URLs online

39%

Quickly encode or decode URLs online with this easy-to-use tool. Convert your data to and from URL-encoded format with advanced options and instant results.

regexpal.com favicon

Test regular expressions live, instantly

39%

Test and debug your JavaScript and PCRE regular expressions online. Instantly see matches and results as you type, making regex learning and troubleshooting easier.

httpstatus.io favicon

Check website status codes instantly

39%

Check HTTP status codes for any URL to quickly see if a website is up, down, or redirecting. Simple tool for web developers and site owners.

guardsquare.com favicon

Protect and optimize your Java & Android code

37%

ProGuard protects and optimizes Java and Android apps by shrinking, obfuscating, and securing code for better performance and enhanced security.

bundlephobia.com favicon

See npm package sizes instantly

37%

Check the size and performance impact of any npm JavaScript package before adding it to your project. Quickly find out how dependencies affect your bundle.

scalatest.org favicon

Test Scala and Java code with ease

37%

ScalaTest is a flexible testing tool for Scala and Java projects, helping you write and run tests easily with deep integration into popular development tools.

mamp.info favicon

Run a local web server on your Mac with ease

37%

Set up a local web server on your Mac with MAMP to develop and test websites using Apache, MySQL, and PHP. Free and pro versions available.

bugherd.com favicon

Collect website feedback with point-and-click

37%

BugHerd helps teams and clients give website feedback and report bugs easily with point-and-click comments. Simplify web project collaboration and reviews.

square1.io favicon

Transform ideas into digital products with experts

37%

Square1 helps businesses transform digitally with expert web and mobile software development, digital strategy, and payment platform solutions.

freeformatter.com favicon

Format and validate code instantly online

35%

Access free online tools for developers to format, validate, minify, convert, and analyze code and data in formats like JSON, XML, HTML, and more.

happycog.com favicon

Full-service digital agency for web & marketing

35%

Happy Cog is a digital agency offering web development, design, branding, and digital marketing services to help businesses grow online.

rustybrick.com favicon

Custom web and app solutions for your business

35%

RustyBrick offers web design, development, and branding services in New York, helping businesses build custom websites, apps, and marketing strategies.

htmlpreview.github.io favicon

View GitHub HTML files instantly in your browser

33%

Preview HTML files from GitHub or Bitbucket directly in your browser without downloading or cloning the repository. Simple and instant HTML rendering.

validator.schema.org favicon

Validate your site's structured data instantly

33%

Check your website's structured data for errors and improve SEO with this easy-to-use schema markup validator. Supports multiple languages.

w-shadow.com favicon

WordPress tips and web development insights

33%

A blog sharing tips, guides, and insights on web development, software business, and WordPress tools for developers and site owners.

dougal.gunters.org favicon

WordPress tips and web development insights

31%

A personal blog sharing insights on WordPress, web development, and coding projects, with plugin tips and tech musings from Dougal Campbell.

vansteinengroentjes.nl favicon

Tailored software solutions for your business

31%

Van Stein & Groentjes creates custom software for web, Android, and iOS, helping businesses manage orders, invoices, and digital processes.

regextester.com favicon

Test and debug regex instantly online

31%

Test and debug regular expressions online for JavaScript, PHP, and PCRE. Instantly see matches and results to refine your regex with ease.