Code Diff Checker

Compare two code snippets side by side. Highlights added, removed, and modified lines across any programming language — Python, JavaScript, Go, SQL, shell scripts, and more.

Compare Code Snippets Instantly

Paste two versions of a function, file, or config and see exactly what changed — line by line. No git required. Useful for code reviews, debugging, and comparing LLM output against your original.

  • Any language: Works with Python, JavaScript, TypeScript, Go, Rust, SQL, shell, and any text-based format
  • Line-level and inline diff: See which lines changed and exactly which characters within them
  • Side-by-side or unified view: Switch to match your preference
  • Private: Code never leaves your browser — safe for proprietary code

When to Use a Code Diff Tool

  • Reviewing LLM suggestions: Paste your original function and the AI-suggested version to see exactly what changed before accepting it
  • Manual code review: Compare a colleague's snippet against the original when you don't have git context available
  • Debugging regressions: Paste the working and broken version of a function to isolate what changed between the last working state and now
  • Config comparison: Compare nginx.conf, sshd_config, or environment-specific config files between servers
  • Database migration review: Compare SQL migration scripts before and after edits to verify the exact changes

Related Diff Tools

Frequently Asked Questions

How is this different from git diff?

git diff requires files to be tracked in a git repository and shows changes relative to a previous commit or staged state. This tool lets you diff any two text blocks — code snippets, clipboard contents, or output from different sources — without a repository. It's useful when you have two versions of something that aren't in git, like comparing a snippet from documentation against your implementation, or reviewing a suggested refactor from an AI tool.

Can I compare minified or obfuscated code?

Yes, but the diff will be hard to read — a single changed character in a minified file shows the entire line as modified. For meaningful comparison of minified code, first pretty-print or format both versions (use the JSON formatter for JSON, a code formatter for JS/CSS), then diff the formatted output. The diff tool works on whatever text you paste — formatting quality determines readability.

Does the diff ignore comments and whitespace?

By default, all content is compared exactly. Use the "ignore whitespace" option to skip leading/trailing whitespace differences — useful when code was reformatted but not changed functionally. Comment-only changes will still show as diffs. There's no language-aware mode that strips comments automatically, since "comments" means different things across languages (#, //, /* */, --, etc.).