Sentry and Grafana are frequently mentioned together in monitoring discussions, but they solve different problems at different layers of the stack. Sentry tells you what went wrong in your application code and why. Grafana shows you how your infrastructure and services are performing over time. Understanding this distinction is key to building effective observability.
Sentry excels at application-level error tracking. When an exception occurs in your production application, Sentry captures the full stack trace, request context, user information, browser/device details, and the sequence of events (breadcrumbs) leading to the error. Its source map support for JavaScript means you see the original source code, not minified gibberish. This code-level context makes debugging specific errors dramatically faster.
Grafana's strength is metric visualization and correlation. It connects to dozens of data sources — Prometheus, InfluxDB, Elasticsearch, CloudWatch, PostgreSQL, and many more — and provides a powerful dashboarding system that lets you visualize metrics from across your entire infrastructure in one place. Time-series graphs, heatmaps, alerts, and annotations help teams understand system behavior over time.
Performance monitoring exists in both tools but at different depths. Sentry's performance monitoring traces individual requests through your application, showing exactly which function or database query is slow. Grafana's performance monitoring shows aggregate metrics — request rates, latency percentiles, error rates — across your services. Sentry answers 'why is this specific request slow?'; Grafana answers 'is our service meeting its SLOs?'
Alerting capabilities differ in scope. Sentry alerts on application errors with intelligent grouping — similar errors are grouped together so you see 'UserLoginError (423 events)' rather than 423 individual alerts. Grafana's alerting system works across any metric from any data source, enabling infrastructure-level alerts like 'CPU usage above 90% for 5 minutes' or 'disk space below 10%.'
The deployment model differs. Sentry offers both a hosted SaaS (sentry.io) and a self-hosted open-source option. Grafana is open-source at its core with Grafana Cloud as the managed offering. Both self-hosted options are widely used, though Grafana's self-hosting is more common in the enterprise observability stack.
Integration depth varies by use case. Sentry has deep SDK integrations for application frameworks — React, Django, Flask, Express, Spring, Rails, and dozens more. These SDKs automatically capture errors, transactions, and context without manual instrumentation. Grafana integrates at the data layer, connecting to whatever systems already expose metrics.
For frontend developers, Sentry is particularly valuable. Session replay shows exactly what the user did before encountering an error. Web Vitals monitoring tracks Core Web Vitals performance. Release tracking correlates errors with specific deployments. Grafana has less visibility into frontend application behavior.