---
title: "Attributes"
description: "Attributes automatically enrich your telemetry with typed key-value data. Use them to add business context that you can then filter and search in Sentry."
url: https://docs.sentry.io/platforms/dart/enriching-events/attributes/
---

# Attributes | Sentry for Dart

Available since: `v9.9.0`

**Attributes** are key-value pairs you can attach to your telemetry (like [spans](https://docs.sentry.io/platforms/dart/tracing/instrumentation/custom-instrumentation.md) (SDK version `9.23.0`+), [logs](https://docs.sentry.io/platforms/dart/logs.md), and [metrics](https://docs.sentry.io/platforms/dart/metrics.md)).

Common uses include subscription tier, feature flags, or any business context that helps you filter and query your telemetry.

Each attribute value is created with a typed `SentryAttribute` factory:

| Factory                          | Dart Type      |
| -------------------------------- | -------------- |
| `SentryAttribute.string(v)`      | `String`       |
| `SentryAttribute.int(v)`         | `int`          |
| `SentryAttribute.bool(v)`        | `bool`         |
| `SentryAttribute.double(v)`      | `double`       |
| `SentryAttribute.stringArray(v)` | `List<String>` |
| `SentryAttribute.intArray(v)`    | `List<int>`    |
| `SentryAttribute.boolArray(v)`   | `List<bool>`   |
| `SentryAttribute.doubleArray(v)` | `List<double>` |

Attributes on spans require [stream mode](https://docs.sentry.io/platforms/dart/tracing/streamed-spans.md). In stream mode, spans have no contexts, data, or tags — everything is a typed attribute, so `setData` and `setTag` are replaced by `setAttribute` and `setAttributes`.

Attributes on logs and metrics don't require stream mode and work by default.

## [Add Attributes to the Current Scope](https://docs.sentry.io/platforms/dart/enriching-events/attributes.md#add-attributes-to-the-current-scope)

Use `Sentry.setAttributes` to attach attributes to the current scope. This is the easiest way to enrich everything at once:

```dart
Sentry.setAttributes({
  'org_id': SentryAttribute.string(user.orgId),
  'user_tier': SentryAttribute.string(user.tier),
  'service': SentryAttribute.string('checkout'),
});
```

## [Setting Attributes on Individual Telemetry](https://docs.sentry.io/platforms/dart/enriching-events/attributes.md#setting-attributes-on-individual-telemetry)

You can also attach attributes to a single span, log, or metric directly, which is useful when the data only makes sense for that one item.

### [Spans](https://docs.sentry.io/platforms/dart/enriching-events/attributes.md#spans)

In stream mode, you can set attributes when starting a span:

```dart
await Sentry.startSpan(
  'process-order',
  (_) async {
    await processOrder();
  },
  attributes: {
    'sentry.op': SentryAttribute.string('queue.process'),
    'order.id': SentryAttribute.string('abc-123'),
    'order.item_count': SentryAttribute.int(5),
    'order.priority': SentryAttribute.bool(true),
  },
);
```

Or add them to an already running span with `setAttribute` or `setAttributes`. Use `removeAttribute` to remove an attribute:

```dart
await Sentry.startSpan('handle-request', (span) async {
  span.setAttribute(
    'http.response.status_code',
    SentryAttribute.int(200),
  );

  span.setAttributes({
    'http.route': SentryAttribute.string('/api/users'),
    'user.id': SentryAttribute.string('user-42'),
  });

  await handleRequest();
});
```

See [Add Attributes](https://docs.sentry.io/platforms/dart/tracing/streamed-spans.md#add-attributes) for more on span attributes.

### [Logs](https://docs.sentry.io/platforms/dart/enriching-events/attributes.md#logs)

Pass attributes to any `Sentry.logger` call:

```dart
Sentry.logger.info('User ${user.username} added ${product.name} to cart.', attributes: {
  'user': SentryAttribute.string(user.username),
  'product': SentryAttribute.string(product.name),
});
```

See [Logs](https://docs.sentry.io/platforms/dart/logs.md) for more.

### [Metrics](https://docs.sentry.io/platforms/dart/enriching-events/attributes.md#metrics)

Pass attributes in the `attributes` parameter of any metric. Each metric has a 2KB size limit for attributes:

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

See [Metrics](https://docs.sentry.io/platforms/dart/metrics.md) for more.