Table of Contents
LinearB Metrics Glossary
A complete guide to how LinearB defines and calculates core engineering metrics. Use this glossary to align your teams on what each metric means, how it is calculated, and why it matters. Delivery Me…
A complete guide to how LinearB defines and calculates core engineering metrics. Use this glossary to align your teams on what each metric means, how it is calculated, and why it matters.
Delivery Metrics
Cycle Time
Definition
Time from when coding begins on a branch to when the work is released.
Cycle Time is composed of four measurable sub-phases:
Coding Time, Pickup Time, Review Time, and
Deploy Time.
Calculation
The average duration of the four sub-phases across all completed branches within the selected time range or iteration.
Why it matters
Cycle Time is a core measure of delivery speed. It reflects your team’s ability to deliver software efficiently end-to-end. Understanding where time accumulates helps you identify bottlenecks, drive process improvements, and improve overall flow efficiency.
2026 Benchmarks
Based on the 2026 LinearB Software Engineering Benchmarks Report (8.1M+ PRs across 4,800 organizations, calculated at the 75th percentile/P75):
2026 Benchmarks (hours, P75)
Elite: < 25 hours
Good: 25 – 72 hours
Fair: 73 – 161 hours
Needs focus: > 161 hours
See LinearB's full 2026 Benchmarks Report .
Use these ranges as a reference point when comparing your team’s Cycle Time. If your workspace uses a different aggregation method (Average, Median, P75, P90), focus on direction of change over time as well as how you compare to these bands.
Coding Time
Definition
Time developers spend actively coding before a pull request is opened.
Calculation
From the first commit on a branch until the PR is created:
Coding Time = pr_created_at − first_commit_timestamp
Draft / WIP PR behavior
Draft or WIP pull requests are excluded from Cycle Time and their duration is counted as Coding Time instead.
For configuration details, see Draft Pull Requests .
Why it matters
Coding Time indicates how long work stays in progress before review. Prolonged Coding Time can hide risk (large, unreviewed changes) and make it harder to spot misaligned or blocked work early.
Configuration
An Admin user can choose how Coding Time begins:
- By first commit (default)
- By issue state moving to In Progress
Configuration path: Settings → Advanced (Coding Time configuration near the bottom).
Pickup Time
Definition
Time between when a PR is opened (or moved from draft to active) and the first non-author review activity.
Calculation
From PR creation to the first reviewer comment or review:
Pickup Time = first_comment_at − pr_created_at
- If a PR is approved or merged without comments, Pickup Time is measured from PR open time to the first approval or merge timestamp.
- Comments from the PR author do not count as review and are ignored for this transition.
Why it matters
Pickup Time captures reviewer responsiveness and prioritization. Long Pickup Time often indicates review bottlenecks, unclear ownership, or overloaded reviewers.
Review Time
Definition
Time from the start of review to when a PR is merged.
Calculation
From the first non-author review activity until the PR is merged:
Review Time = pr_merged_at − first_comment_at
- Comments or reviews from the PR author (self-reviews) are ignored when determining the review start.
- If a PR is approved or merged without any review activity, LinearB records Review Time as 0 for that PR.
Why it matters
Review Time reflects how smoothly code review is happening. Long Review Time can signal unclear ownership, overloaded reviewers, or process friction.
Deploy Time
Definition
Time from when a PR is merged until it is released to production.
Calculation
From merge to production release:
Deploy Time = released_at − pr_merged_at
Why it matters
Deploy Time shows how long it takes to move merged work into the hands of users. Long Deploy Time can indicate manual release processes, complex approvals, or slow CI/CD.
Configuration
An Admin user can configure how LinearB detects releases under: Settings → Advanced → Release Detection. Supported methods include:
- Using Git tags on a release branch.
- Pull requests into a dedicated release branch (e.g.,
main,master). - Direct merges into a dedicated release branch.
- API Integration (Deployment API).
Time to Approve
Definition
Time from the start of review to the first approval.
Calculation
From first reviewer comment/review to first approval:
Time to Approve = first_approval_at − first_reviewer_comment_or_review_at
- PRs approved without any prior comments or explicit reviews are treated as having Time to Approve of 0.
Why it matters
Time to Approve highlights how quickly reviewers make a decision once they start engaging with the PR. Long Time to Approve can point to unclear standards, over-scoped PRs, or misaligned expectations.
Time to Merge
Definition
Time from first approval until the PR is merged.
Calculation
From first approval to merge:
Time to Merge = pr_merged_at − first_approval_at
Why it matters
Time to Merge highlights friction after approval—such as waiting for CI, additional approvals, or release coordination. Large gaps here can hide delays that aren’t visible in review throughput alone.
Quality Metrics
Pull Request Size (PR Size)
Definition
The final difference between the head branch and the base branch when the pull request is created. It reflects the net change in code after all modifications have been applied.
Calculation
Final diff at PR creation:
PR Size = additions + deletions + modifications
Why it matters
Smaller PRs are easier and safer to review. Large PRs tend to increase review time, reduce review quality, and raise the risk of defects in production.
Review Depth
Definition
The average number of comments made during review. This includes general comments, suggestions, or requests for changes.
Calculation
Average comments per PR over the selected period.
Why it matters
Review Depth reflects how thorough reviews are. Too low can indicate rubber-stamping; too high may signal overly large or unclear PRs.
PRs Merged Without Review
Definition
The number of PRs merged with no review activity.
Calculation
Count of merged PRs where the review count is 0 during the selected period.
Why it matters
High “no review” merges can reveal bypassed controls and correlate with production issues or defects.
New Code Ratio
Definition
The percentage of changed lines that are net new code (as opposed to modifications of existing lines).
Calculation
New Code Ratio = new_lines_added ÷ total_lines_changed
Why it matters
Indicates the balance between creating new functionality vs. modifying existing code. Useful for understanding how much of the team’s effort is focused on net new value.
Refactor Ratio
Definition
The ratio of legacy code (for example, older than a configured age threshold) that was modified in the selected period.
Calculation
Refactor Ratio = legacy_code_lines_changed ÷ total_lines_changed
Why it matters
Shows investment in maintainability and technical debt reduction. Higher refactor activity can be healthy when aligned with strategy.
Rework Ratio
Definition
The ratio of recently-changed code (for example, changed within a recent time window) that is modified again in the selected period.
Calculation
Rework Ratio = recent_code_lines_changed ÷ total_lines_changed
Why it matters
High rework can signal churn or instability in new work. It is a quality-risk signal that can indicate unclear requirements or rushed changes.
PR Maturity Ratio
Definition
A measure of how much a PR changes after it is first opened, indicating how “ready” it was at submission time.
Conceptual Calculation
LinearB compares the state of the branch at two points:
- At PR creation – the initial state of the branch.
- At PR closure – the final state after all changes.
The ratio reflects the extent of changes made after initial submission (for example, additional commits to address feedback, fixes, or rework).
Why it matters
PR Maturity highlights how well-prepared a PR is before being submitted.
- Quality indicator: Shows the readiness of work at submission.
- Efficient reviews: Higher maturity often leads to smoother, faster reviews.
- Process insight: Low maturity can signal a need for better pre-review checks, clearer acceptance criteria, or smaller PRs.
Throughput Metrics
Code Changes
Definition
Total lines of code changed during the selected period.
Calculation
Code Changes per day = (additions + modifications + deletions) ÷ days_in_period
Why it matters
Provides a high-level view of code volume and output. If you are 2–3 days into an iteration and this value remains low, it may indicate poorly defined tasks or hidden bottlenecks.
Commits
Definition
Total number of commits made in the selected period.
Calculation
Commits per day = total_commits ÷ days_in_period
Why it matters
Shows commit activity levels and can be used to understand participation patterns over time.
PRs Opened
Definition
Number of new pull requests created in the selected period.
Calculation
PRs Opened per day = total_prs_created ÷ days_in_period
Why it matters
Measures how much work is entering the review pipeline and helps balance intake vs. completion.
Merge Frequency
Definition
Average number of PRs merged per day.
Calculation
Merge Frequency = total_prs_merged ÷ days_in_period
Why it matters
A cadence signal for delivery momentum. A healthy merge frequency often correlates with smaller, more frequent releases.
Deploy Frequency
Definition
Average number of deployments per day.
Calculation
Deploy Frequency = total_releases ÷ days_in_period
Why it matters
One of the DORA metrics; it indicates how often code reaches users. Higher deploy frequency (with healthy quality) is associated with more adaptable, resilient teams.
Done Branches
Definition
Branches that reached a “Merged” or “Released” state in the selected period.
Calculation
Count of branches with status in {merged, released}.
Why it matters
Tracks closure rate and helps ensure work is not left lingering as long-lived branches.
Coding Days*
Definition
Normalized count of developer-days with code activity.
Calculation
For each day, measure the fraction of team members who committed at least once. Aggregate across the selected period to produce a normalized value.
Why it matters
Highlights engagement consistency and broad participation across the team, rather than only counting raw volume.
*Metric available by request. To request, please contact your LinearB team.
Balance & Work Breakdown Metrics
Active Days
Definition
Unique days with any Git activity (commits, PRs, reviews) in the selected period.
Calculation
Count of unique days where developer activity > 0.
Why it matters
Shows participation patterns over time and can highlight potential burnout (activity every day) or idle periods.
Active Branches
Definition
Number of branches considered active (not merged or deleted) during the period.
When a branch is “active”
- It has commits, PRs, or merges within the configured stale period (from any contributor).
- It has not been merged or closed by the end of the specified time window.
Calculation
Count of branches with status = active.
Why it matters
Active Branches act as a proxy for WIP. Too many active branches can slow development flow and increase context switching.
Work Breakdown
Definition
The distribution of work types (for example, New Code, Refactor, Rework) over the selected period.
Why it matters
Helps you see whether engineering effort is aligned with strategy—such as balancing new feature work, maintenance, and refactoring.
Project Management / DORA Metrics
MTTR (Mean Time to Restore)
Definition
Average time to restore service after a production incident.
Conceptual Calculation
Average duration from incident start to incident resolution:
MTTR = (sum of all incident resolution durations) ÷ (number of incidents)
Why it matters
A core DORA metric that captures resilience and recovery speed. Lower MTTR indicates the team can quickly mitigate customer impact when failures occur.
Configuration
An Admin can define which issues represent incidents and which fields correspond to start/end times under: Company Settings → Project Management → Incidents.
CFR (Change Failure Rate)
Definition
Percentage of releases that cause a failure or incident.
Calculation
CFR = failed_releases ÷ total_releases
Why it matters
CFR is a DORA metric that measures release quality and change stability. High CFR indicates that deployments frequently introduce production problems.
Configuration
An Admin can define how LinearB recognizes incidents for CFR under: Company Settings → Project Management → Incidents.
AI-Specific Metrics
AI Code Review Metrics
Definition
Quantitative indicators for AI-assisted code reviews—for example, how often AI suggestions are accepted, ignored, or followed by further changes.
Example calculation approaches
(Depending on your specific AI setup)
- Share of PRs that include AI review suggestions.
- Ratio of accepted vs. dismissed AI suggestions.
- Follow-up changes or rework on AI-assisted PRs.
Why it matters
AI Code Review metrics help you understand AI adoption and impact: how often AI is used, whether it is trusted, and where it adds—or fails to add—value in the review process.
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