Software Alternatives, Accelerators & Startups

YAMLValidator.dev VS CSSViewer

Compare YAMLValidator.dev VS CSSViewer and see what are their differences

YAMLValidator.dev logo YAMLValidator.dev

Validate YAML syntax and schemas for Kubernetes, Docker Compose, GitHub Actions, and more. Free, private, runs entirely client-side (browser extension and website).

CSSViewer logo CSSViewer

A simple CSS property viewer
  • YAMLValidator.dev
    Image date //
    2026-04-05
  • YAMLValidator.dev Extension popup
    Extension popup //
    2026-04-05
  • YAMLValidator.dev Enhanced GitHub YAML viewing โ€” collapsible code blocks
    Enhanced GitHub YAML viewing โ€” collapsible code blocks //
    2026-04-05

YAML Validator is a free, privacy-first tool for validating, formatting, and viewing YAML files โ€” available as a Chrome extension and a website.

What it does

  • Syntax validation โ€” catch indentation errors, duplicate keys, and malformed YAML instantly
  • Schema validation โ€” validate against 11+ real-world schemas with auto-detection:
    • Kubernetes, Docker Compose, Helm Chart
    • GitHub Actions, GitLab CI, CircleCI, Azure Pipelines, Bitbucket Pipelines
    • Ansible, OpenAPI 3.0, Swagger 2.0
  • Multi-document support โ€” validate files with multiple YAML documents separated by ---
  • Smart error reporting โ€” highlights the exact line, shows a gutter marker, and scrolls to the error
  • GitHub integration โ€” adds collapsible code blocks to YAML files on GitHub, making large configs easier to navigate

How it works

Paste or type YAML into the editor. YAML Validator auto-detects the schema (e.g., spots apiVersion + kind and picks Kubernetes) and validates both syntax and structure in one click. If the detected schema doesn't match, it suggests the right one with a single-click switch.

Privacy & performance

Everything runs client-side โ€” your files never leave your machine. No accounts, no server processing, no data collection. Works offline, loads instantly.

Built for DevOps workflows

Whether you're writing Kubernetes manifests, debugging a CI pipeline, or reviewing a Helm chart on GitHub โ€” YAML Validator catches errors before they reach production. The Chrome extension currently has around 800 users worldwide.

Available in 54 languages.

  • CSSViewer Landing page
    Landing page //
    2023-09-30

YAMLValidator.dev

Platforms
Google Chrome Desktop MacOS Linux Windows
Release Date
2024 November

YAMLValidator.dev features and specs

  • Schema Validation
    Kubernetes, Docker Compose, GitHub Actions, GitLab CI, CircleCI, Azure Pipelines, Bitbucket Pipelines, Ansible, Helm Chart, OpenAPI 3.0, Swagger 2.0
  • GitHub Integration
    Syntax highlighting and code folding
  • Multi-Document YAML
    Supports files with multiple documents separated by ---
  • Auto-Detection
    Automatically identifies the schema based on file content

CSSViewer features and specs

  • Ease of Use
    CSSViewer offers a simple and intuitive interface that allows users to easily inspect CSS properties of web elements by hovering over them.
  • Quick Access
    The extension provides quick access to CSS properties without the need to open the browser's developer tools, saving time for developers and designers.
  • Detailed Information
    CSSViewer displays detailed CSS information, such as font, color, and box properties, which can be useful for debugging or learning CSS.
  • Lightweight Tool
    The extension is lightweight and doesn't require significant system resources, making it a convenient tool for front-end developers.

Possible disadvantages of CSSViewer

  • Limited Functionality
    CSSViewer is limited to viewing CSS properties and does not allow users to edit them directly or offer any advanced features available in full-featured developer tools.
  • Browser Compatibility
    The extension is explicitly designed for Google Chrome, which means users of other browsers may need to look for alternatives.
  • No Updates or Support
    Users have reported that CSSViewer lacks regular updates, which may lead to compatibility issues with newer versions of Chrome or fails to support newer CSS features.
  • Potential Security Risks
    As with any third-party extension, users need to be cautious about permissions and potential security risks associated with installing and using such tools.

Analysis of YAMLValidator.dev

Overall verdict

  • YAMLValidator.dev is a solid, lightweight tool for quickly checking and formatting YAML files, making it a reliable choice for developers who work with configuration files regularly.

Why this product is good

  • Fast, browser-based validation with no installation required
  • Clear error messages that pinpoint syntax issues by line
  • Supports formatting and beautifying YAML for better readability
  • Free to use and privacy-friendly since validation happens client-side
  • Simple, clean interface that is easy for beginners and experts alike

Recommended for

  • Developers working with Kubernetes, Docker Compose, or CI/CD config files
  • DevOps engineers who frequently edit YAML manifests
  • Beginners learning YAML syntax and structure
  • Anyone needing a quick, no-signup way to catch YAML errors before deployment

Category Popularity

0-100% (relative to YAMLValidator.dev and CSSViewer)
Developer Tools
18 18%
82% 82
Design Tools
0 0%
100% 100
Kubernetes
100 100%
0% 0
Development
0 0%
100% 100

Questions & Answers

As answered by people managing YAMLValidator.dev and CSSViewer.

What makes your product unique?

YAMLValidator.dev's answer

It validates YAML against real schemas โ€” generic YAML, Kubernetes, Docker Compose, GitHub Actions, GitLab CI, Helm, OpenAPI, and more โ€” not just syntax checking. Everything runs client-side, so your config files never leave your machine. It works both as a Chrome extension (with GitHub integration for collapsible code blocks) and as a standalone website.

How would you describe the primary audience of your product?

YAMLValidator.dev's answer

DevOps engineers, SREs, and backend developers who work with Kubernetes manifests, Docker Compose files, CI/CD pipelines (GitHub Actions, GitLab CI, CircleCI, Azure Pipelines), Helm charts, and OpenAPI specs. Anyone who edits YAML config files and wants instant validation without leaving the browser.

What's the story behind your product?

YAMLValidator.dev's answer

I am software engineer and extension(and lately site) was made out of frustration with debugging YAML indentation errors in CircleCI schemes and Kubernetes deployments. A misplaced space in a YAML file can break an entire deployment, and generic text editors don't catch schema-level mistakes. YAML Validator was built to catch those errors before they reach production โ€” directly in the browser, with zero setup.

Which are the primary technologies used for building your product?

YAMLValidator.dev's answer

JavaScript/TypeScript, CodeMirror (editor), js-yaml (parsing), Ajv (JSON Schema validation), Lit (web components), and Tailwind CSS. Built as a Chrome Extension (Manifest V3) with Vite as the bundler. Schemas are pre-compiled at build time for performance and CSP compliance

Who are some of the biggest customers of your product?

YAMLValidator.dev's answer

YAML Validator is a free, open-use tool โ€” it doesn't track users or require accounts. It's used by individual developers and teams working with Kubernetes, Docker, and CI/CD pipelines. As a privacy-first browser tool, there's no customer list by design. The browser extension currently has around 800 users worldwide.

Why should a person choose your product over its competitors?

YAMLValidator.dev's answer

There's simply no other Chrome extension that does this. Most online YAML tools are web-only, require an internet connection, and only check syntax. YAML Validator runs entirely offline, validates against 11+ schemas with auto-detection (Kubernetes, Docker Compose, GitHub Actions, and more), and enriches GitHub with collapsible code blocks for YAML files. It's fast, private, and requires zero setup โ€” install and go.

User comments

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Social recommendations and mentions

Based on our record, CSSViewer seems to be more popular. It has been mentiond 5 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

YAMLValidator.dev mentions (0)

We have not tracked any mentions of YAMLValidator.dev yet. Tracking of YAMLValidator.dev recommendations started around Apr 2026.

CSSViewer mentions (5)

  • 7 Must Have Chrome Extensions for JavaScript Developers
    The "CSS Viewer" Chrome extension is a handy tool for JavaScript developers seeking to inspect and analyze CSS styles on web pages. With a simple click on the extension's icon in the Chrome toolbar, it provides a user-friendly interface that allows you to hover over any element on a webpage and instantly view its corresponding CSS properties and values. - Source: dev.to / about 3 years ago
  • 20 Top Best Chrome Extensions for Web Developers in 2022
    CSS Viewer is a simple but very effective Chrome extension for web developers. As its name implies, this addon shows you the CSS properties of a given page wherever you hover your mouse. A small popup window appears showing you the CSS data that makes up the element youโ€™re pointing at. - Source: dev.to / about 4 years ago
  • Top 10 Chrome Extensions for Web Developers in 2022
    1 - CSSViewer : It allows to show the CSS properties of element on any webpage, you just hover your mouse on it . A small window appears showing you the CSS data . - Source: dev.to / over 4 years ago
  • 21 Chrome Extension for web developer and designer
    CSSViewer helps us to view CSS properties of an object in a web page in the most general way such as color, font, size, position... You just need to select this utility and hover your mouse over the object that they want. If you want, the CSS information will automatically appear. CSSViewer. - Source: dev.to / about 5 years ago
  • Awesome Tools and Technologies I Use as a Developer!
    CSSViewer - For viewing and inspecting CSS on a page. - Source: dev.to / over 5 years ago

What are some alternatives?

When comparing YAMLValidator.dev and CSSViewer, you can also consider the following products

YAMLine - Yamline offers a suite of online YAML tools, including a Comparator, Formatter, Validator, and various converters for formats like JSON and Properties.

CSS Peeper - Smart CSS viewer tailored for Designers.

ValidKube - ValidKube combines the best open-source tools to help ensure Kubernetes YAML best practices, hygiene & security.

Tailwind CSS - A utility-first CSS framework for rapidly building custom user interfaces.

yamlfmt - An extensible command line tool or library to format yaml files. - GitHub - google/yamlfmt: An extensible command line tool or library to format yaml files.

Unused CSS finder - Crawl your website and find unused CSS