Review time

The time it takes from the first review to merging the PR. First review can be comments, approval or request for changes.

Computation of the metric

1. Start Time: Begins when the review process is initiated (usually indicated by the first reviewer changing the PR state to “In review”).
2. End Time: Ends when the PR is merged into the target branch, signifying completion of the code review.
3. Review Time is calculated as the duration between the Start Time and End Time for each PR.

Industry benchmarks

1. Low: 0-1d
2. Medium: 1d-3d
3. High: >3d

Dashboards where this metric is used

1. Developer Summary
2. Dev Metric Grid
3. Dev Cycle Time

Use cases

1. Review time helps to understand the amount of time spent in doing the first review. If the time is too high, it may indicate heavy work load with the reviewers.
2. It can also indicate a lack of experienced engineers available to review PRs on time.
3. Use this to identify PRs that have very high review times and engage with the submitter & reviewer to diagnose what caused the long review cycle
4. For complex PRs, encourage f2f/online meetings to complete the code review instead of async reviews which increase the review cycles aka ping-pong
5. Diagnose if the reviewer & submitter share the same understanding of the requirement
6. Consider instituting a grooming/problem-solving session before the coding begins to reduce review time