Question 1

Is LocalDiff.dev safe for comparing sensitive code?

Accepted Answer

Yes. All diff comparisons happen locally in your browser. Your code and text data never leaves your machine and is never uploaded to any server.

Question 2

Do I need to create an account?

Accepted Answer

No. LocalDiff.dev works without any sign-up, login, or registration. Just open it and start comparing.

Question 3

What file types does LocalDiff.dev support?

Accepted Answer

LocalDiff.dev supports all text-based file types including JavaScript, TypeScript, Python, Go, Rust, Java, JSON, YAML, XML, HTML, CSS, SQL, Markdown, and more.

Question 4

How does the AI merge feature work?

Accepted Answer

The AI merge feature uses Google Gemini to analyze conflicting code blocks in context and suggests the most logical merged version. Only the specific text chunks involved are sent to the API.

Question 5

Is LocalDiff.dev free to use?

Accepted Answer

Yes. LocalDiff.dev is completely free. The free tier supports 10 comparisons per day. The service is supported by non-intrusive advertising and affiliate links.

Question 6

What is the character or file size limit?

Accepted Answer

Each panel supports up to 100,000 characters. For most code files and documents this is more than sufficient. Enterprise users with a valid key have no limit.

Question 7

Does LocalDiff.dev work offline?

Accepted Answer

The core diff functionality works offline after the page loads. The AI merge feature and URL content fetching require an internet connection.

Question 8

What programming languages does syntax highlighting support?

Accepted Answer

LocalDiff.dev auto-detects and highlights JavaScript, TypeScript, Python, Go, Rust, Java, C, C++, C#, PHP, Ruby, Swift, Kotlin, JSON, YAML, XML, HTML, CSS, SQL, Markdown, and more.

Question 9

Can I compare PDFs or Word documents?

Accepted Answer

LocalDiff.dev compares plain text and code. For PDFs or Word docs, first export or copy the text content, then paste it into the panels.

Question 10

How is LocalDiff.dev different from GitHub's diff view?

Accepted Answer

LocalDiff.dev is for ad-hoc comparison of any text — no git repository required. It adds word-level diff highlighting, AI-powered merge, and syntax highlighting for 20+ languages, all without uploading your content to any server.