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AI Tools/AI Code Review

AI Code Review

Get instant code analysis — bugs, security, performance, best practices. 100% local AI.

AI · LOCALBug detectionSecurity scanPerformanceBest practices
Model:
Auto-loads on use (~1400MB)

Your Code

1 lines · 0 chars

Paste your code and click "Review Code" to get an AI-powered analysis.

🐛 Bug Risk🔒 Security Performance🎨 Code Style Best Practice🔧 Maintainability
Data Source & Legal Disclaimer
Effective: 2026
Sources: Browser-side processing (no external API)

This tool runs 100% in your browser. All computation happens locally on your device — your input is never uploaded to any server. Results are for reference only.

See all data sources & update policy →

How AI code review works — illustrated

Paste a snippet and the reviewer first auto-detects the language from syntax fingerprints — Python, TypeScript, Java, Go, and more. It then sends your code to a local language model instructed to act as an expert reviewer, asking for a strict JSON object: a one-paragraph summary, a quality score out of 10, and a list of issues. Each issue is tagged with a severity (critical, warning, suggestion, praise) and a category (bug, security, performance, style, best-practice, maintainability) plus an optional line number and a concrete fix. If the model's reply doesn't parse cleanly, the tool retries with a simpler prompt before giving up. Everything runs in your browser, so proprietary source code never leaves your machine.

From code paste to a scored review report
Local AI code reviewYour codeauto-detect languagefunction getData(id) { var q = "SELECT…" db.execute(q)…→ JavaScriptimport → Pythonstd:: → C++Local LLM reviewerLlama 3.2 / SmolLM2bug · security · perf · stylestrict JSON outputsummary + score + issuesretry with simpler promptReview reportscore + tagged issues6Quality score /10SQL injection (L2)var instead of constGood error handling

Code is language-detected, analyzed by a local LLM as an expert reviewer, and parsed into a structured report with a score and severity-tagged issues.

Worked example — Diego's vulnerable lookup

Diego pastes a 14-line JavaScript function that builds a SQL query by string concatenation and hits Review. The tool auto-detects JavaScript and runs the local Llama-3.2-1B model.

  1. Analyze:The model flags the string-concatenated query as a critical SQL-injection risk on line 2, plus a warning that "var" should be "const" and a praise note for the async callback pattern.
  2. Score:It assigns 6/10 — code works but the security issue keeps it out of good territory.
  3. Fix:Each issue carries a concrete suggestion: use parameterized queries, prefer const, and early-return instead of nesting.
  4. Iterate:Diego applies the fixes and reruns the review, watching the score climb to 9/10 with the injection finding gone.
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To review code: paste your code snippet, the AI analyzes it for bugs, SQL injection, XSS vulnerabilities, performance bottlenecks, and best practice violations — all locally in your browser.

FreeToolHub AI Code Review is a free browser-based tool that analyzes code for bugs, security vulnerabilities, and performance issues, no signup.

About this tool

What is this tool?

Get instant AI-powered code review. Find bugs, security issues, performance problems, and best practice violations. 100% in-browser. Free.

Bug detectionSecurity scanPerformanceBest practices

What Is the AI Code Review Tool?

The AI Code Review tool analyzes your code for bugs, security vulnerabilities, performance issues, code style violations, and best practice deviations. It uses a browser-based AI model (SmolLM2) to understand your code semantically and provide actionable feedback. Unlike traditional static analysis tools that rely on predefined rules, the AI can identify context-specific issues and suggest improvements that a human reviewer would catch.

Who Should Use This Tool?

This tool is for developers of all levels — from beginners learning best practices to senior engineers doing a quick self-review before submitting a pull request. It is especially useful for solo developers and open-source contributors who do not have a team of reviewers available. The tool supports JavaScript, TypeScript, Python, Java, C++, Go, Rust, and many other languages with automatic language detection.

How Does This Tool Work?

Paste your code and select a language (or use auto-detect). The tool sends your code to the SmolLM2 AI model running locally in your browser. The model analyzes the code and returns a structured review with a quality score (1-10), a summary, and a list of issues categorized by severity (critical, warning, suggestion, praise) and type (bug, security, performance, style, best practice, maintainability). Each issue includes a description and suggested fix.

Frequently Asked Questions

Is my code sent to a server?

No. The AI model (SmolLM2) runs 100% in your browser using WebGPU or WASM. Your code is processed locally and never leaves your device. There is no signup, no upload, and no data collection. This makes it safe for reviewing proprietary or confidential code.

What languages are supported?

The tool supports JavaScript, TypeScript, Python, Java, C++, C#, Go, Rust, Ruby, PHP, Swift, Kotlin, Scala, SQL, HTML, CSS, Shell, and more. Language detection is automatic, but you can also manually select the language for more accurate analysis.

How accurate is the AI code review?

The AI model provides a good first-pass review that catches common issues like SQL injection, unused variables, missing error handling, and performance anti-patterns. However, it is not a replacement for human review — always verify the suggestions and use your judgment. The tool is best used as a quick self-check before submitting code for peer review.

What types of issues does it find?

The tool identifies issues in six categories: Bugs (logic errors, null references, race conditions), Security (injection, XSS, hardcoded credentials), Performance (unnecessary loops, memory leaks, inefficient algorithms), Code Style (naming, formatting, consistency), Best Practices (error handling, design patterns), and Maintainability (complexity, duplication, documentation).

Is this code review tool free?

Yes, 100% free with no signup, no API key, no usage limits, and no watermark. The AI model runs in your browser, so there are no server costs.

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