Paste any git diff and get an AI-powered code review in seconds — potential issues, logic analysis, security flags, and reviewer questions. No account, no subscription.
Flags unintended behavior changes, incorrect conditionals, and edge cases not handled by the new code.
Identifies exposed secrets, SQL injection vectors, XSS risk, unvalidated user input, and auth bypasses in the diff.
Spots N+1 query patterns, unnecessary re-renders, large loops over growing datasets, and synchronous operations that should be async.
Notes logic changes that lack corresponding test coverage and suggests what edge cases to test.
Flags inconsistencies with patterns visible in the surrounding code — naming conventions, error handling approaches, code organization.
Frames findings as questions to ask the author — "Is this behavior change intentional?" — matching how a senior developer would review the PR.
| Tool | Cost for 100 reviews/month | Account required | Works with any git host |
|---|---|---|---|
| AI Diff Summarizer | $0.08–$0.30 | No | Yes |
| GitHub Copilot Enterprise | $39/user/month (flat) | GitHub account + billing | GitHub only |
| CodeRabbit Pro | $12–24/user/month (flat) | GitHub/GitLab account | GitHub + GitLab |
| GitLab Duo | Included in Ultimate ($39/user/mo) | GitLab Ultimate account | GitLab only |
| Sourcegraph Cody | Free tier (rate-limited) | Account required | Yes (via IDE) |
AI Diff Summarizer cost assumes Claude Haiku ($0.80/MTok input). 100 reviews × avg 1,000 input tokens = 100k tokens = $0.08. With Sonnet 4.6 ($3/MTok): ~$0.30.
AI Diff Summarizer is free to use (no account, no subscription). You provide your own Anthropic API key — you pay only for the API calls you make, typically $0.0008–$0.003 per review. The Anthropic API has $5 of free credit for new accounts, which covers ~5,000 typical PR reviews with Haiku.
Logic errors, unintended behavior changes, missing edge cases, security patterns (exposed secrets, SQL injection, XSS), performance regressions (N+1 queries, large loops), inconsistencies with surrounding code style, and missing tests for changed logic. Findings are framed as reviewer questions, matching the tone of a senior developer's PR review.
AI excels at pattern recognition, consistency checks, and catching common mistakes — and can review 1,000 lines of diff in seconds. However, it lacks business context. The best use is as a first-pass reviewer that flags obvious issues before a human does the final review, reducing the reviewer's cognitive load by 30–50%.
AI Diff Summarizer at ~$0.08–$0.30/month for 100 reviews (pay-per-use Anthropic API). The next cheapest is CodeRabbit at $12/user/month. AI Diff Summarizer is 40–150x cheaper for teams that need review summaries rather than IDE autocomplete integration.
AI Diff Summarizer has no backend — your diff goes directly from your browser to the Anthropic API using your own key. No server sees your code. Anthropic does not use API inputs for training by default. For most teams with standard data handling policies, the privacy profile is comparable to or better than GitHub Copilot or other SaaS code review tools.