Bug Reopen Rate

A rising reopen rate often points to rushed fixes, missing regression checks, or unclear acceptance criteria on the original ticket.

Reopen % = (reopened ÷ closed) × 100.

Tip: Keep “Reopened Bugs” and “Closed Bugs” on the same basis (period, units, and population) before calculating Bug Reopen Rate.

Cluster: Software Testing hub · Professional KPIs · Percentage guide

Reopen rate measures how often closed defects come back because the fix failed or verification was incomplete.

Enter reopened bugs and total closed bugs in the same period.

Bugs closed then reopened in the period
Bugs marked closed/resolved in the same period

Reopen Rate %

Understanding Bug Reopen Rate

How we calculate. Reopen % = (reopened ÷ closed) × 100. The form uses the same arithmetic as the worked examples on this page. See our methodology and accuracy policy.

Real-world scenario: A typical Bug Reopen Rate case uses reopened bugs 16 and closed bugs 200. Enter the same figures below to reproduce the worked path.

What is Bug Reopen Rate?

A rising reopen rate often points to rushed fixes, missing regression checks, or unclear acceptance criteria on the original ticket.

  • Count unique reopen events or unique bugs reopened—pick one rule
  • High reopen: invest in fix verification and root-cause analysis
  • Pair with rework rate when you also track time spent re-fixing

The Formula

Bug Reopen Rate
Reopen % = (Reopened bugs ÷ Closed bugs) × 100

Worked Example

Scenario: In a month, 200 bugs were closed. 16 of those were later reopened.
Step 1: Reopened = 16
Step 2: Closed = 200
Step 3: (16 ÷ 200) × 100 = 8%
Answer: Bug reopen rate is 8%.

Common Use Cases

  • Fix quality: monitor incomplete resolutions
  • Verification process: strengthen QA sign-off on closures
  • Team coaching: review reopened tickets for patterns

Pro Tips

  • Exclude reopen for new scope when the ticket was expanded, not failed
  • Track by severity — critical reopens are costly
  • Check environment mismatch before blaming the fix

Limitations: Bug Reopen Rate results are estimates for learning and QA planning—not contractual SLAs. Align definitions with your org’s quality glossary before executive reporting.

FAQ

Does reopen count if the same bug is reopened twice?

Decide up front: either count unique bugs or count reopen events. Keep the rule stable for trends.

Is reopen rate a developer KPI?

Use it as a process signal, not a blame metric. Causes often span requirements, environments, and testing.

Authoritative References

For software quality metrics definitions, consult established engineering sources:

  • ISTQB — software testing glossary and practices
  • ISO/IEC 25010 — systems and software quality models
  • IEEE — software engineering standards