Issues & Events

How Sentry groups errors into issues and tracks individual occurrences as events.

Sentry captures individual error occurrences as events and automatically groups related events into issues. This distinction is fundamental to how you triage and resolve problems in your application.

Events

An event is a single occurrence captured by the Sentry SDK. Every time an error is thrown, a transaction completes, or a session is recorded, Sentry receives one event.

Each event contains:

• Stack trace — the call stack at the moment the error occurred
• Breadcrumbs — a log of actions that led up to the event (navigation, clicks, network requests, console output)
• Context — runtime information like OS, browser, app version, and device
• Tags — key-value pairs you attach to categorize and filter events
• User — identity of the affected user (if configured)
• Request — HTTP request details for server-side events

Event types

Type	Description
Error	An exception or unhandled error in your application
Transaction	A performance trace measuring the duration of a request or operation
Profile	A sampling profile of function-level performance
Replay	A session replay capturing user interactions in the browser
Cron check-in	A heartbeat from a scheduled job or cron monitor
Feedback	User-submitted feedback attached to a session

Issues

An issue is a group of events that Sentry considers to be the same problem. When Sentry receives an event, it computes a fingerprint based on the error type, message, and stack trace, then looks for an existing issue with the same fingerprint. If one exists, the event is added to it. If not, a new issue is created.

This grouping means you see “this error has occurred 1,243 times across 87 users” rather than thousands of individual entries.

Issue types

Sentry detects many types of issues across different categories:

Error issues

• Unhandled exceptions and crashes

Performance issues (detected automatically)

• N+1 Query
• Slow DB Query
• Consecutive DB Queries
• DB on Main Thread
• File I/O on Main Thread
• Large Render Blocking Asset
• Uncompressed Asset
• Large HTTP payload
• Consecutive HTTP
• N+1 API Call
• HTTP/1.1 Overhead
• Endpoint Regression
• Function Regression

Frontend issues

• Rage Click Detected
• Hydration Error Detected
• Web Vitals

Mobile issues

• File I/O on Main Thread
• Image Decoding on Main Thread
• JSON Decoding on Main Thread
• Regex on Main Thread
• Frame Drop

Cron issues

• Missed check-ins, failed jobs, and timeout violations

Feedback

• User-submitted crash reports and feedback

Issue lifecycle

Issues move through states as you investigate and resolve them:

New

The issue was just created — Sentry has never seen this fingerprint before. New issues surface at the top of the issue stream by default.

Ongoing (Unresolved)

The issue continues to receive events and has not been resolved or archived. Most active issues are in this state.

Escalating

Sentry detected that the issue’s event volume increased significantly after a period of quiet. Escalating issues are surfaced prominently in the UI.

Resolved

Someone marked the issue as resolved, or it was automatically resolved after a configured period without new events. If the same error recurs, the issue reopens as a regression.

Regressed

The issue was previously resolved but new events arrived. Regressions are a signal that a fix didn’t fully work or the problem came back in a new release.

Archived

The issue is muted — either until it escalates, until a condition is met, or indefinitely. Archived issues do not appear in the default issue stream.

Issue priority

Sentry automatically assigns a priority to each issue based on signals like error frequency, number of affected users, and escalation patterns.

Priority	When assigned
Critical	Highest severity — high volume, widespread user impact, or rapidly escalating
High	Significant impact, requires prompt attention
Medium	Moderate impact; default for most new issues
Low	Minimal impact or rare occurrence

You can manually override the priority on any issue.

The issue detail page

When you open an issue, you see a consolidated view of everything Sentry knows about it:

• Event count and user count — how often it’s occurring and how many users it affects
• First seen / Last seen — the time range of the issue
• Stack trace — the most recent event’s stack trace, with source code inline if source maps or debug symbols are configured
• Breadcrumbs — the sequence of events leading up to the crash
• Tags — aggregated tag values across all events (useful for finding patterns like “this only happens on Chrome 120”)
• User — the affected user for the current event
• Similar issues — related issues that may be caused by the same root problem
• Activity — a history of comments, status changes, and assignments

Searching and filtering issues

The issue stream supports a query language for narrowing down issues:

is:unresolved assigned:me
is:unresolved !has:release
is:unresolved times_seen:>100
is:unresolved user.email:[e-mail]

You can filter by status (is:unresolved, is:resolved), assignee, release version, environment, tags, and many other attributes. Saved searches let you bookmark commonly used filters.

Use the Environment selector at the top of the issue stream to filter events by environment (production, staging, etc.) without changing your search query.