Cursor
GitHub Copilot
Claude Code
Augment Code
Factory
CodeRabbit
Synlets
Devin is an autonomous agent that solves engineering tasks through the use of its own shell, code editor, and web browser.

W3C Markup Validation Service
Json List
Code Beautify JSON Validator
HTML Validator
Schema Validator
Total Validator
Free HTML, CSS, JSON & XML validator with 12 tools and instant quality scores from 0 to 100.

Which is more popular?
Based on our record, Devin seems to be more popular. It has been mentioned 1 time since March 2021.
Website, pricing, platforms and company facts side by side.
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D
Devin
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|---|---|---|
| Website | cognition.com | validatehtml.com |
| Pricing | — | |
| Company | — | Startup from France · 1 - 9 employees · 2026 |
| Listed in |
In their own words, as submitted to SaaSHub.

No description of Devin yet.
ValidateHTML is a free suite of 12 web validation tools in one place. Paste code or enter a URL to validate HTML, CSS, JSON, XML, check meta tags, Open Graph data, accessibility, robots.txt, and more. Every validation returns a quality score from 0 to 100 so you know exactly where you stand. No...
What each product offers, as listed by its team.

No features have been listed yet.
An editorial look at what each product does well and who it suits.

Overall verdict
Why this product is good
Recommended for
Overall verdict
Why this product is good
Recommended for
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Devin review: is it a better AI coding agent than Cursor?
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How often each product is chosen within a category, 0–100% relative to the other.

As answered by people managing Devin and ValidateHTML.
ValidateHTML's answer:
12 validation tools in one place with an instant quality score from 0 to 100. No signup, no limits, completely free. Paste code or enter a URL and get results in seconds.
ValidateHTML's answer:
Instead of opening 5 different tabs (W3C for HTML, JSONLint for JSON, separate tools for meta tags, Open Graph, accessibility), ValidateHTML combines everything in one interface. Plus you get a quality score that tells you exactly where you stand.
ValidateHTML's answer:
Web developers, frontend engineers, and SEO specialists who need to validate code quality before deploying. Also useful for freelancers and agencies managing multiple client sites.
ValidateHTML's answer:
I was tired of opening 5 or 6 different tabs every time I needed to validate my code before deploying. W3C for HTML, JSONLint for JSON, random sites for meta tags. So I built one tool that does everything, with a quality score to instantly know where you stand.
ValidateHTML's answer:
Next.js, React, TypeScript, Tailwind CSS, deployed on Vercel.
ValidateHTML's answer:
Independent web developers, Freelance frontend engineers and Small web agencies.
Share your experience with using Devin and ValidateHTML. For example, how are they different and which one is better?
Recommendations tracked on public social media and blogs since March 2021.

Cognition, "Introducing Devin, the first AI software engineer" (March 12, 2024): the launch post; the 13.86% SWE-bench self-report and unassisted-evaluation details. - Source: dev.to / 3 months ago
Tracking ValidateHTML since Mar 2026.
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Transform hours of debugging into seconds with a single command. Experience coding at thought-speed with Claude's AI that understands your entire codebase—no more context switching, just breakthrough results.
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Code Beauty’s JSON Validator or JSON Lint is easy to use tool to copy, paste and validate JSON data.
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