Code Analysis

ExplainThis helps you understand unfamiliar programs faster. The review engine turns snippets into clear walkthroughs that stay accurate.

Review Modes

Standard Mode

This is the default mode. It gives you a balanced walkthrough of your code. You will see how things work, how the code is structured, and what details matter most. Pick this when you want a thorough, big-picture overview.

// Example code
function calculateTotal(items) {
  return items.reduce((sum, item) => sum + item.price, 0);
}

This function calculates the total price of items in a shopping cart. It uses the reduce method to iterate through the items array, accumulating the sum of item prices, starting from 0.

Beginner Mode

This mode is built for learners. It is also great if you are working in a language you do not know well. You get step-by-step breakdowns with extra context about language features and core programming ideas.

Performance Mode

This mode looks at how fast your code runs. It checks time complexity and memory usage, then points out where you can optimize. Use it when speed matters most.

Security Mode

This mode scans your code for security problems. It checks for common vulnerabilities and follows proven security patterns. Use it when your app handles passwords, personal data, or payments.

Inspection Features

Contextual Understanding: The engine looks beyond the snippet you paste. It also considers imports, dependencies, and nearby files. This means the walkthrough matches your real project, not just the code in isolation.
Language-Specific Insights: Every language has its own idioms and patterns. For example, Python feedback highlights list comprehensions. JavaScript feedback covers async/await. The advice always fits the language you are using.
Interactive Examples: Each explanation includes a clear, step-by-step walkthrough. You can follow along line by line. This makes it easy to learn what each part of the code does.
Best Practices: You get clear, actionable tips for improving your code. These come from widely accepted standards and proven design patterns. See our best practices guide for more detail.

Putting Results to Work

Here are some ways developers put these insights to work every day:

Auto-generate docs — Turn an explanation into a README section or inline comments. This saves time on documentation.
Speed up code reviews — Share an explanation link with your reviewer. They can focus on design instead of puzzling out what the code does.
Learn new languages — Paste code you have never seen before. Read a plain-English breakdown of what every line does.
Improve quality — Follow the suggestions to make your code cleaner and easier to maintain. If you are dealing with legacy code, our post on what technical debt is and how to manage it is a great companion read.
Audit for security — Run Security mode before you deploy. It catches vulnerabilities before they reach production.

Next: Language Support

Review Modes

Standard Mode

// Example code
function calculateTotal(items) {
  return items.reduce((sum, item) => sum + item.price, 0);
}

This function calculates the total price of items in a shopping cart. It uses the reduce method to iterate through the items array, accumulating the sum of item prices, starting from 0.

Beginner Mode

Performance Mode

This mode looks at how fast your code runs. It checks time complexity and memory usage, then points out where you can optimize. Use it when speed matters most.

Security Mode

This mode scans your code for security problems. It checks for common vulnerabilities and follows proven security patterns. Use it when your app handles passwords, personal data, or payments.

Inspection Features

Contextual Understanding: The engine looks beyond the snippet you paste. It also considers imports, dependencies, and nearby files. This means the walkthrough matches your real project, not just the code in isolation.

Language-Specific Insights: Every language has its own idioms and patterns. For example, Python feedback highlights list comprehensions. JavaScript feedback covers async/await. The advice always fits the language you are using.

Interactive Examples: Each explanation includes a clear, step-by-step walkthrough. You can follow along line by line. This makes it easy to learn what each part of the code does.

Best Practices: You get clear, actionable tips for improving your code. These come from widely accepted standards and proven design patterns. See our best practices guide for more detail.

Putting Results to Work

Here are some ways developers put these insights to work every day:

Auto-generate docs — Turn an explanation into a README section or inline comments. This saves time on documentation.

Speed up code reviews — Share an explanation link with your reviewer. They can focus on design instead of puzzling out what the code does.

Learn new languages — Paste code you have never seen before. Read a plain-English breakdown of what every line does.

Improve quality — Follow the suggestions to make your code cleaner and easier to maintain. If you are dealing with legacy code, our post on what technical debt is and how to manage it is a great companion read.

Audit for security — Run Security mode before you deploy. It catches vulnerabilities before they reach production.