---
title: "Metrics"
description: "Metrics allow you to send, view and query counters, gauges and measurements from your Sentry-configured apps to track application health and drill down into related traces, logs, and errors."
url: https://docs.sentry.io/platforms/dart/metrics/
---

# Set Up Metrics | Sentry for Dart

With Sentry Metrics, you can send counters, gauges, and distributions from your applications to Sentry. Once in Sentry, these metrics can be viewed alongside relevant errors, and searched using their individual attributes.

This feature is currently in open beta. Features in beta are still in progress and may have bugs.

## [Requirements](https://docs.sentry.io/platforms/dart/metrics.md#requirements)

Metrics are supported in Sentry Dart SDK version `9.11.0` and above.

## [Usage](https://docs.sentry.io/platforms/dart/metrics.md#usage)

### [Metric Types](https://docs.sentry.io/platforms/dart/metrics.md#metric-types)

| Type           | Use For                                      |
| -------------- | -------------------------------------------- |
| `count`        | Events (orders, clicks, API calls)           |
| `gauge`        | Current values (queue depth, connections)    |
| `distribution` | Value ranges (response times, payload sizes) |

No setup required beyond SDK initialization.

```dart
import 'package:sentry/sentry.dart';

// Count occurrences
Sentry.metrics.count('orders_created', 1);

// Track current values
Sentry.metrics.gauge('active_connections', 42);

// Track distributions
Sentry.metrics.distribution(
  'api_latency',
  187,
  unit: 'millisecond',
);
```

### [Attributes](https://docs.sentry.io/platforms/dart/metrics.md#attributes)

#### [Filtering and Grouping](https://docs.sentry.io/platforms/dart/metrics.md#filtering-and-grouping)

Attributes let you filter and group metrics in Sentry. Use them for:

* Environment segmentation
* Feature flag tracking
* User tier analysis

Each metric has a **2KB size limit**. If you exceed this, the metric will be dropped.

```dart
Sentry.metrics.count(
  'api_calls',
  1,
  attributes: {
    'endpoint': SentryAttribute.string('/api/orders'),
    'user_tier': SentryAttribute.string('pro'),
    'region': SentryAttribute.string('us-west'),
  },
);
```

#### [Scope Attributes](https://docs.sentry.io/platforms/dart/metrics.md#scope-attributes)

Use scope APIs to set attributes that apply to all metrics while the scope is active.

```dart
// Add attributes to the global scope
Sentry.setAttributes({'is_admin': SentryAttribute.bool(true)});

// All scope attributes are added to metrics
Sentry.metrics.count('clicks', 1);
Sentry.metrics.gauge(
  'time_since_refresh',
  4,
  unit: 'second',
);
```

#### [Units](https://docs.sentry.io/platforms/dart/metrics.md#units)

For `gauge` and `distribution` metrics, specify a unit to help Sentry display values in a human-readable format.

Common units: `millisecond`, `second`, `byte`, `kilobyte`, `megabyte`. Use `SentryMetricUnit` to conveniently access supported units in Dart. See [supported units](https://develop.sentry.dev/sdk/foundations/data-model/attributes/#units) for the full list.

```dart
Sentry.metrics.distribution(
  'response_time',
  187.5,
  unit: SentryMetricUnit.millisecond,
);

Sentry.metrics.gauge(
  'memory_usage',
  1024,
  unit: SentryMetricUnit.byte,
);
```

## [Options](https://docs.sentry.io/platforms/dart/metrics.md#options)

### [beforeSendMetric](https://docs.sentry.io/platforms/dart/metrics.md#beforesendmetric)

Filter or modify metrics before sending. Return `null` to drop a metric.

```dart
import 'package:sentry/sentry.dart';

await Sentry.init((options) {
  options.dsn = '___PUBLIC_DSN___';
  options.beforeSendMetric = (metric) {
    // Drop specific metrics
    if (metric.attributes.containsKey('debug')) {
      return null;
    }

    // Return the metric to send it
    return metric;
  };
});
```

### [Disable Metrics](https://docs.sentry.io/platforms/dart/metrics.md#disable-metrics)

Set `enableMetrics: false` to disable metrics collection entirely.

```dart
import 'package:sentry/sentry.dart';

// Disable metrics
await Sentry.init((options) {
  options.dsn = '___PUBLIC_DSN___';
  options.enableMetrics = false;
});
```

## [Default Attributes](https://docs.sentry.io/platforms/dart/metrics.md#default-attributes)

Sentry automatically attaches these attributes to every metric:

| Attribute                            | Description                     | Context             |
| ------------------------------------ | ------------------------------- | ------------------- |
| `sentry.environment`                 | Environment from SDK config     | Always              |
| `sentry.release`                     | Release version from SDK config | Always              |
| `sentry.sdk.name`                    | SDK name                        | Always              |
| `sentry.sdk.version`                 | SDK version                     | Always              |
| `os.name`                            | Operating system name           | If available        |
| `os.version`                         | Operating system version        | If available        |
| `user.id`, `user.name`, `user.email` | User identifiers                | If available        |
| `sentry.replay_id`                   | Session replay ID               | If replay available |