diff --git a/.github/ISSUE_TEMPLATE/blank.yaml b/.github/ISSUE_TEMPLATE/blank.yaml
index 9a3b2920320..003463ae736 100644
--- a/.github/ISSUE_TEMPLATE/blank.yaml
+++ b/.github/ISSUE_TEMPLATE/blank.yaml
@@ -144,6 +144,7 @@ body:
       - otelcol.receiver.vcenter
       - otelcol.receiver.zipkin
       - otelcol.storage.file
+      - prometheus.echo
       - prometheus.enrich
       - prometheus.exporter.apache
       - prometheus.exporter.azure
diff --git a/.github/ISSUE_TEMPLATE/bug_report.yaml b/.github/ISSUE_TEMPLATE/bug_report.yaml
index a91fc4e793a..407a881000a 100644
--- a/.github/ISSUE_TEMPLATE/bug_report.yaml
+++ b/.github/ISSUE_TEMPLATE/bug_report.yaml
@@ -144,6 +144,7 @@ body:
       - otelcol.receiver.vcenter
       - otelcol.receiver.zipkin
       - otelcol.storage.file
+      - prometheus.echo
       - prometheus.enrich
       - prometheus.exporter.apache
       - prometheus.exporter.azure
diff --git a/.github/ISSUE_TEMPLATE/docs.yaml b/.github/ISSUE_TEMPLATE/docs.yaml
index 5b927b7ab5d..979dd4fb0c2 100644
--- a/.github/ISSUE_TEMPLATE/docs.yaml
+++ b/.github/ISSUE_TEMPLATE/docs.yaml
@@ -147,6 +147,7 @@ body:
       - otelcol.receiver.vcenter
       - otelcol.receiver.zipkin
       - otelcol.storage.file
+      - prometheus.echo
       - prometheus.enrich
       - prometheus.exporter.apache
       - prometheus.exporter.azure
diff --git a/.github/ISSUE_TEMPLATE/feature_request.yaml b/.github/ISSUE_TEMPLATE/feature_request.yaml
index ab8c4e54da5..aa3361d08ae 100644
--- a/.github/ISSUE_TEMPLATE/feature_request.yaml
+++ b/.github/ISSUE_TEMPLATE/feature_request.yaml
@@ -144,6 +144,7 @@ body:
       - otelcol.receiver.vcenter
       - otelcol.receiver.zipkin
       - otelcol.storage.file
+      - prometheus.echo
       - prometheus.enrich
       - prometheus.exporter.apache
       - prometheus.exporter.azure
diff --git a/.github/ISSUE_TEMPLATE/proposal.yaml b/.github/ISSUE_TEMPLATE/proposal.yaml
index 91a85c121a9..2c953a2550d 100644
--- a/.github/ISSUE_TEMPLATE/proposal.yaml
+++ b/.github/ISSUE_TEMPLATE/proposal.yaml
@@ -144,6 +144,7 @@ body:
       - otelcol.receiver.vcenter
       - otelcol.receiver.zipkin
       - otelcol.storage.file
+      - prometheus.echo
       - prometheus.enrich
       - prometheus.exporter.apache
       - prometheus.exporter.azure
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0a39d94478c..76c40c06c9d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,8 @@ Main (unreleased)
 
 - Add htpasswd file based authentication for `otelcol.auth.basic` (@pkarakal)
 
+- Add `prometheus.echo` component for local inspection of Prometheus metrics. The component writes received metrics to stdout in Prometheus exposition format, enabling easier debugging and testing of metrics flow. (@iamrajiv)
+
 ### Enhancements
 
 - update promtail converter to use `file_match` block for `loki.source.file` instead of going through `local.file_match`. (@kalleep)
diff --git a/docs/sources/reference/compatibility/_index.md b/docs/sources/reference/compatibility/_index.md
index 55ae1649ab0..dc2ecf0713c 100644
--- a/docs/sources/reference/compatibility/_index.md
+++ b/docs/sources/reference/compatibility/_index.md
@@ -187,6 +187,7 @@ The following components, grouped by namespace, _export_ Prometheus `MetricsRece
 {{< /collapse >}}
 
 {{< collapse title="prometheus" >}}
+- [prometheus.echo](../components/prometheus/prometheus.echo)
 - [prometheus.enrich](../components/prometheus/prometheus.enrich)
 - [prometheus.relabel](../components/prometheus/prometheus.relabel)
 - [prometheus.remote_write](../components/prometheus/prometheus.remote_write)
diff --git a/docs/sources/reference/components/prometheus/prometheus.echo.md b/docs/sources/reference/components/prometheus/prometheus.echo.md
new file mode 100644
index 00000000000..f866f99e178
--- /dev/null
+++ b/docs/sources/reference/components/prometheus/prometheus.echo.md
@@ -0,0 +1,122 @@
+---
+canonical: https://grafana.com/docs/alloy/latest/reference/components/prometheus/prometheus.echo/
+description: Learn about prometheus.echo
+labels:
+  stage: general-availability
+  products:
+    - oss
+title: prometheus.echo
+---
+
+# `prometheus.echo`
+
+The `prometheus.echo` component receives Prometheus metrics and writes them to stdout in Prometheus exposition format.
+This component is useful for debugging and testing the flow of metrics through a pipeline, allowing you to see exactly what metrics are being received at a particular point in your configuration.
+
+## Usage
+
+```alloy
+prometheus.echo "<LABEL>" {
+}
+```
+
+## Arguments
+
+You can use the following arguments with `prometheus.echo`:
+
+| Name     | Type     | Description                                                     | Default | Required |
+| -------- | -------- | --------------------------------------------------------------- | ------- | -------- |
+| `format` | `string` | The output format for metrics. Must be `text` or `openmetrics`. | `text`  | no       |
+
+The `format` argument controls how metrics are encoded when written to stdout:
+
+* `text` - Uses the Prometheus text exposition format (default).
+* `openmetrics` - Uses the OpenMetrics text format.
+
+## Blocks
+
+The `prometheus.echo` component doesn't support any blocks. You can configure this component with arguments.
+
+## Exported fields
+
+The following fields are exported and can be referenced by other components:
+
+| Name       | Type              | Description                                               |
+| ---------- | ----------------- | --------------------------------------------------------- |
+| `receiver` | `MetricsReceiver` | A value that other components can use to send metrics to. |
+
+## Component health
+
+`prometheus.echo` is only reported as unhealthy if given an invalid configuration.
+In those cases, exported fields retain their last healthy values.
+
+## Debug information
+
+`prometheus.echo` doesn't expose any component-specific debug information.
+
+## Debug metrics
+
+`prometheus.echo` doesn't expose any component-specific debug metrics.
+
+## Example
+
+This example creates a metrics generation and inspection pipeline:
+
+```alloy
+prometheus.exporter.unix "default" {
+}
+
+prometheus.scrape "demo" {
+  targets    = prometheus.exporter.unix.default.targets
+  forward_to = [prometheus.echo.debug.receiver]
+}
+
+prometheus.echo "debug" {
+  format = "text"
+}
+```
+
+In this example:
+
+1. The `prometheus.exporter.unix` component exposes system metrics.
+1. The `prometheus.scrape` component scrapes those metrics.
+1. The `prometheus.echo` component receives the scraped metrics and writes them to stdout in Prometheus text format.
+
+When you run this configuration, you'll see the metrics being written to stdout, which is useful to:
+
+* Debug metric collection issues
+* Verify metric labels and values
+* Test metric transformations
+* Understand the structure of metrics in your pipeline
+
+### Example with OpenMetrics format
+
+```alloy
+prometheus.scrape "demo" {
+  targets = [
+    {"__address__" = "localhost:9090"},
+  ]
+  forward_to = [prometheus.echo.debug.receiver]
+}
+
+prometheus.echo "debug" {
+  format = "openmetrics"
+}
+```
+
+This example outputs metrics using the OpenMetrics format instead of the traditional Prometheus text format.
+
+<!-- START GENERATED COMPATIBLE COMPONENTS -->
+
+## Compatible components
+
+`prometheus.echo` has exports that can be consumed by the following components:
+
+- Components that consume [Prometheus `MetricsReceiver`](../../../compatibility/#prometheus-metricsreceiver-consumers)
+
+{{< admonition type="note" >}}
+Connecting some components may not be sensible or components may require further configuration to make the connection work correctly.
+Refer to the linked documentation for more details.
+{{< /admonition >}}
+
+<!-- END GENERATED COMPATIBLE COMPONENTS -->
diff --git a/internal/component/all/all.go b/internal/component/all/all.go
index 3f739dbe63f..8ab87472d77 100644
--- a/internal/component/all/all.go
+++ b/internal/component/all/all.go
@@ -127,6 +127,7 @@ import (
 	_ "github.com/grafana/alloy/internal/component/otelcol/receiver/vcenter"                 // Import otelcol.receiver.vcenter
 	_ "github.com/grafana/alloy/internal/component/otelcol/receiver/zipkin"                  // Import otelcol.receiver.zipkin
 	_ "github.com/grafana/alloy/internal/component/otelcol/storage/file"                     // Import otelcol.storage.file
+	_ "github.com/grafana/alloy/internal/component/prometheus/echo"                          // Import prometheus.echo
 	_ "github.com/grafana/alloy/internal/component/prometheus/enrich"                        // Import prometheus.enrich
 	_ "github.com/grafana/alloy/internal/component/prometheus/exporter/apache"               // Import prometheus.exporter.apache
 	_ "github.com/grafana/alloy/internal/component/prometheus/exporter/azure"                // Import prometheus.exporter.azure
diff --git a/internal/component/prometheus/echo/echo.go b/internal/component/prometheus/echo/echo.go
new file mode 100644
index 00000000000..e65e582057b
--- /dev/null
+++ b/internal/component/prometheus/echo/echo.go
@@ -0,0 +1,527 @@
+package echo
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"sort"
+	"sync"
+	"time"
+
+	"github.com/go-kit/log"
+	"github.com/grafana/alloy/internal/component"
+	"github.com/grafana/alloy/internal/featuregate"
+	"github.com/grafana/alloy/internal/runtime/logging/level"
+	dto "github.com/prometheus/client_model/go"
+	"github.com/prometheus/common/expfmt"
+	"github.com/prometheus/common/model"
+	"github.com/prometheus/prometheus/model/exemplar"
+	"github.com/prometheus/prometheus/model/histogram"
+	"github.com/prometheus/prometheus/model/labels"
+	"github.com/prometheus/prometheus/model/metadata"
+	"github.com/prometheus/prometheus/storage"
+	"google.golang.org/protobuf/types/known/timestamppb"
+	"k8s.io/utils/ptr"
+)
+
+func init() {
+	component.Register(component.Registration{
+		Name:      "prometheus.echo",
+		Stability: featuregate.StabilityGenerallyAvailable,
+		Args:      Arguments{},
+		Exports:   Exports{},
+		Build: func(opts component.Options, args component.Arguments) (component.Component, error) {
+			return New(opts, args.(Arguments))
+		},
+	})
+}
+
+type Arguments struct {
+	Format string `alloy:"format,attr,optional"`
+}
+
+type Exports struct {
+	Receiver storage.Appendable `alloy:"receiver,attr"`
+}
+
+var DefaultArguments = Arguments{
+	Format: "text",
+}
+
+func (args *Arguments) SetToDefault() {
+	*args = DefaultArguments
+}
+
+var (
+	_ component.Component = (*Component)(nil)
+	_ storage.Appendable  = (*Component)(nil)
+)
+
+type Component struct {
+	opts component.Options
+	mut  sync.RWMutex
+	args Arguments
+}
+
+func New(o component.Options, args Arguments) (*Component, error) {
+	c := &Component{
+		opts: o,
+	}
+	if err := c.Update(args); err != nil {
+		return nil, err
+	}
+	if o.OnStateChange != nil {
+		o.OnStateChange(Exports{Receiver: c})
+	}
+	return c, nil
+}
+
+func (c *Component) Run(ctx context.Context) error {
+	<-ctx.Done()
+	return nil
+}
+
+func (c *Component) Update(args component.Arguments) error {
+	newArgs := args.(Arguments)
+	c.mut.Lock()
+	defer c.mut.Unlock()
+	c.args = newArgs
+	return nil
+}
+
+func (c *Component) Appender(ctx context.Context) storage.Appender {
+	c.mut.RLock()
+	format := c.args.Format
+	c.mut.RUnlock()
+
+	return &echoAppender{
+		logger:      c.opts.Logger,
+		componentID: c.opts.ID,
+		format:      format,
+		samples:     make(map[string]sample),
+		exemplars:   make(map[string]seriesExemplar),
+		histograms:  make(map[string]seriesHistogram),
+		metadata:    make(map[string]metadata.Metadata),
+	}
+}
+
+type echoAppender struct {
+	logger      log.Logger
+	componentID string
+	format      string
+	mut         sync.Mutex
+
+	samples    map[string]sample
+	exemplars  map[string]seriesExemplar
+	histograms map[string]seriesHistogram
+	metadata   map[string]metadata.Metadata
+}
+
+type sample struct {
+	Labels         labels.Labels
+	Timestamp      int64
+	Value          float64
+	PrintTimestamp bool
+}
+
+type seriesExemplar struct {
+	Labels   labels.Labels
+	Exemplar exemplar.Exemplar
+}
+
+type seriesHistogram struct {
+	Labels    labels.Labels
+	Histogram histogram.Histogram
+}
+
+func (a *echoAppender) Append(ref storage.SeriesRef, l labels.Labels, t int64, v float64) (storage.SeriesRef, error) {
+	a.mut.Lock()
+	defer a.mut.Unlock()
+
+	key := l.String()
+	a.samples[key] = sample{
+		Labels:         l.Copy(),
+		Timestamp:      t,
+		Value:          v,
+		PrintTimestamp: t > 0,
+	}
+
+	if ref == 0 {
+		ref = storage.SeriesRef(len(a.samples))
+	}
+	return ref, nil
+}
+
+func (a *echoAppender) AppendExemplar(ref storage.SeriesRef, l labels.Labels, e exemplar.Exemplar) (storage.SeriesRef, error) {
+	a.mut.Lock()
+	defer a.mut.Unlock()
+
+	key := l.String()
+	a.exemplars[key] = seriesExemplar{
+		Labels:   l.Copy(),
+		Exemplar: e,
+	}
+
+	if ref == 0 {
+		ref = storage.SeriesRef(1)
+	}
+	return ref, nil
+}
+
+func (a *echoAppender) AppendHistogram(ref storage.SeriesRef, l labels.Labels, t int64, h *histogram.Histogram, fh *histogram.FloatHistogram) (storage.SeriesRef, error) {
+	a.mut.Lock()
+	defer a.mut.Unlock()
+
+	key := l.String()
+	if h != nil {
+		a.histograms[key] = seriesHistogram{
+			Labels:    l.Copy(),
+			Histogram: *h,
+		}
+	}
+
+	if ref == 0 {
+		ref = storage.SeriesRef(len(a.histograms))
+	}
+	return ref, nil
+}
+
+func (a *echoAppender) UpdateMetadata(ref storage.SeriesRef, l labels.Labels, m metadata.Metadata) (storage.SeriesRef, error) {
+	a.mut.Lock()
+	defer a.mut.Unlock()
+
+	metricName := l.Get(model.MetricNameLabel)
+	if metricName != "" {
+		a.metadata[metricName] = m
+	}
+
+	if ref == 0 {
+		ref = storage.SeriesRef(1)
+	}
+	return ref, nil
+}
+
+func (a *echoAppender) AppendCTZeroSample(ref storage.SeriesRef, l labels.Labels, t, ct int64) (storage.SeriesRef, error) {
+	a.mut.Lock()
+	defer a.mut.Unlock()
+
+	key := l.String()
+	a.samples[key] = sample{
+		Labels:         l.Copy(),
+		Timestamp:      t,
+		Value:          0,
+		PrintTimestamp: t > 0,
+	}
+
+	if ref == 0 {
+		ref = storage.SeriesRef(len(a.samples))
+	}
+	return ref, nil
+}
+
+func (a *echoAppender) AppendHistogramCTZeroSample(ref storage.SeriesRef, l labels.Labels, t, ct int64, h *histogram.Histogram, fh *histogram.FloatHistogram) (storage.SeriesRef, error) {
+	a.mut.Lock()
+	defer a.mut.Unlock()
+
+	key := l.String()
+	if h != nil {
+		a.histograms[key] = seriesHistogram{
+			Labels:    l.Copy(),
+			Histogram: *h,
+		}
+	}
+
+	if ref == 0 {
+		ref = storage.SeriesRef(len(a.histograms))
+	}
+	return ref, nil
+}
+
+func (a *echoAppender) Commit() error {
+	a.mut.Lock()
+	defer a.mut.Unlock()
+
+	families := a.buildMetricFamilies()
+
+	var buf bytes.Buffer
+	var expFormat expfmt.Format
+
+	switch a.format {
+	case "openmetrics":
+		expFormat = expfmt.NewFormat(expfmt.TypeOpenMetrics)
+	case "text", "":
+		expFormat = expfmt.NewFormat(expfmt.TypeTextPlain)
+	default:
+		level.Warn(a.logger).Log("component", a.componentID, "msg", "unknown format, using text", "format", a.format)
+		expFormat = expfmt.NewFormat(expfmt.TypeTextPlain)
+	}
+
+	encoder := expfmt.NewEncoder(&buf, expFormat)
+
+	for _, family := range families {
+		if err := encoder.Encode(family); err != nil {
+			level.Error(a.logger).Log("component", a.componentID, "error", "failed to encode metric family", "family", family.GetName(), "err", err)
+			continue
+		}
+	}
+
+	level.Info(a.logger).Log("component", a.componentID, "metrics", buf.String())
+
+	a.clearStorage()
+
+	return nil
+}
+
+func (a *echoAppender) Rollback() error {
+	a.mut.Lock()
+	defer a.mut.Unlock()
+
+	a.clearStorage()
+
+	return nil
+}
+
+func (a *echoAppender) SetOptions(opts *storage.AppendOptions) {
+}
+
+func (a *echoAppender) clearStorage() {
+	for k := range a.samples {
+		delete(a.samples, k)
+	}
+	for k := range a.exemplars {
+		delete(a.exemplars, k)
+	}
+	for k := range a.histograms {
+		delete(a.histograms, k)
+	}
+	for k := range a.metadata {
+		delete(a.metadata, k)
+	}
+}
+
+func (a *echoAppender) buildMetricFamilies() []*dto.MetricFamily {
+	b := builder{
+		samples:    a.samples,
+		exemplars:  a.exemplars,
+		metadata:   a.metadata,
+		histograms: a.histograms,
+
+		familyLookup: make(map[string]*dto.MetricFamily),
+	}
+	return b.build()
+}
+
+type builder struct {
+	samples    map[string]sample
+	exemplars  map[string]seriesExemplar
+	metadata   map[string]metadata.Metadata
+	histograms map[string]seriesHistogram
+
+	families     []*dto.MetricFamily
+	familyLookup map[string]*dto.MetricFamily
+}
+
+func (b *builder) build() []*dto.MetricFamily {
+	b.buildFamiliesFromMetadata()
+	b.buildMetricsFromSamples()
+	b.buildHistograms()
+	b.assignExemplars()
+	b.sortFamilies()
+
+	return b.families
+}
+
+func (b *builder) buildFamiliesFromMetadata() {
+	for metricName, md := range b.metadata {
+		family := &dto.MetricFamily{
+			Name: ptr.To(metricName),
+			Help: ptr.To(md.Help),
+		}
+
+		family.Type = ptr.To(dto.MetricType_UNTYPED)
+
+		b.families = append(b.families, family)
+		b.familyLookup[metricName] = family
+	}
+}
+
+func (b *builder) buildMetricsFromSamples() {
+	for _, sample := range b.samples {
+		metricName := sample.Labels.Get(model.MetricNameLabel)
+		if metricName == "" {
+			continue
+		}
+
+		family := b.getOrCreateFamily(metricName)
+		metric := &dto.Metric{}
+
+		sample.Labels.Range(func(label labels.Label) {
+			if label.Name != model.MetricNameLabel {
+				metric.Label = append(metric.Label, &dto.LabelPair{
+					Name:  ptr.To(label.Name),
+					Value: ptr.To(label.Value),
+				})
+			}
+		})
+
+		switch family.GetType() {
+		case dto.MetricType_COUNTER:
+			metric.Counter = &dto.Counter{Value: ptr.To(sample.Value)}
+		case dto.MetricType_GAUGE:
+			metric.Gauge = &dto.Gauge{Value: ptr.To(sample.Value)}
+		default:
+			metric.Untyped = &dto.Untyped{Value: ptr.To(sample.Value)}
+		}
+
+		if sample.PrintTimestamp {
+			metric.TimestampMs = ptr.To(sample.Timestamp)
+		}
+
+		family.Metric = append(family.Metric, metric)
+	}
+}
+
+func (b *builder) buildHistograms() {
+	for _, hist := range b.histograms {
+		metricName := hist.Labels.Get(model.MetricNameLabel)
+		if metricName == "" {
+			continue
+		}
+
+		family := b.getOrCreateFamily(metricName)
+		family.Type = ptr.To(dto.MetricType_HISTOGRAM)
+
+		metric := &dto.Metric{}
+
+		hist.Labels.Range(func(label labels.Label) {
+			if label.Name != model.MetricNameLabel {
+				metric.Label = append(metric.Label, &dto.LabelPair{
+					Name:  ptr.To(label.Name),
+					Value: ptr.To(label.Value),
+				})
+			}
+		})
+
+		metric.Histogram = &dto.Histogram{
+			SampleCount: ptr.To(hist.Histogram.Count),
+			SampleSum:   ptr.To(hist.Histogram.Sum),
+		}
+
+		family.Metric = append(family.Metric, metric)
+	}
+}
+
+func (b *builder) assignExemplars() {
+	for _, ex := range b.exemplars {
+		metricName := ex.Labels.Get(model.MetricNameLabel)
+		if metricName == "" {
+			continue
+		}
+
+		family := b.familyLookup[metricName]
+		if family == nil {
+			continue
+		}
+
+		for _, metric := range family.Metric {
+			if b.labelsMatch(ex.Labels, metric.Label) {
+				exemplar := &dto.Exemplar{
+					Value: ptr.To(ex.Exemplar.Value),
+				}
+
+				if ex.Exemplar.HasTs {
+					ts := ex.Exemplar.Ts / 1000
+					exemplar.Timestamp = timestamppb.New(time.Unix(ts, (ex.Exemplar.Ts%1000)*1e6))
+				}
+
+				ex.Exemplar.Labels.Range(func(label labels.Label) {
+					exemplar.Label = append(exemplar.Label, &dto.LabelPair{
+						Name:  ptr.To(label.Name),
+						Value: ptr.To(label.Value),
+					})
+				})
+
+				if metric.Counter != nil {
+					metric.Counter.Exemplar = exemplar
+				} else if metric.Histogram != nil {
+					metric.Histogram.Bucket = append(metric.Histogram.Bucket, &dto.Bucket{
+						Exemplar: exemplar,
+					})
+				}
+				break
+			}
+		}
+	}
+}
+
+func (b *builder) getOrCreateFamily(metricName string) *dto.MetricFamily {
+	if family, exists := b.familyLookup[metricName]; exists {
+		return family
+	}
+
+	family := &dto.MetricFamily{
+		Name: ptr.To(metricName),
+		Type: ptr.To(dto.MetricType_UNTYPED),
+	}
+
+	b.families = append(b.families, family)
+	b.familyLookup[metricName] = family
+	return family
+}
+
+func (b *builder) labelsMatch(seriesLabels labels.Labels, metricLabels []*dto.LabelPair) bool {
+	if seriesLabels.Len() != len(metricLabels)+1 {
+		return false
+	}
+
+	foundErr := seriesLabels.Validate(func(seriesLabel labels.Label) error {
+		if seriesLabel.Name == model.MetricNameLabel {
+			return nil
+		}
+
+		for _, metricLabel := range metricLabels {
+			if seriesLabel.Name == metricLabel.GetName() && seriesLabel.Value == metricLabel.GetValue() {
+				return nil
+			}
+		}
+
+		return errors.New("label not found")
+	})
+
+	return foundErr == nil
+}
+
+func (b *builder) sortFamilies() {
+	sort.Slice(b.families, func(i, j int) bool {
+		return b.families[i].GetName() < b.families[j].GetName()
+	})
+
+	for _, family := range b.families {
+		sort.Slice(family.Metric, func(i, j int) bool {
+			return b.compareMetrics(family.Metric[i], family.Metric[j])
+		})
+	}
+}
+
+func (b *builder) compareMetrics(a, bb *dto.Metric) bool {
+	aLabels := make([]string, 0, len(a.Label))
+	bLabels := make([]string, 0, len(bb.Label))
+
+	for _, label := range a.Label {
+		aLabels = append(aLabels, label.GetName()+"="+label.GetValue())
+	}
+	for _, label := range bb.Label {
+		bLabels = append(bLabels, label.GetName()+"="+label.GetValue())
+	}
+
+	sort.Strings(aLabels)
+	sort.Strings(bLabels)
+
+	for i := 0; i < len(aLabels) && i < len(bLabels); i++ {
+		if aLabels[i] != bLabels[i] {
+			return aLabels[i] < bLabels[i]
+		}
+	}
+
+	return len(aLabels) < len(bLabels)
+}
diff --git a/internal/component/prometheus/echo/echo_test.go b/internal/component/prometheus/echo/echo_test.go
new file mode 100644
index 00000000000..2e93f567e83
--- /dev/null
+++ b/internal/component/prometheus/echo/echo_test.go
@@ -0,0 +1,225 @@
+package echo
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/go-kit/log"
+	"github.com/grafana/alloy/internal/component"
+	"github.com/grafana/alloy/internal/runtime/componenttest"
+	"github.com/prometheus/prometheus/model/labels"
+	"github.com/prometheus/prometheus/storage"
+	"github.com/stretchr/testify/require"
+)
+
+func TestArgumentsDefaults(t *testing.T) {
+	args := Arguments{}
+	args.SetToDefault()
+	require.Equal(t, DefaultArguments, args)
+}
+
+func TestComponent_Creation(t *testing.T) {
+	ctx := componenttest.TestContext(t)
+
+	comp, err := New(component.Options{
+		ID:     "test",
+		Logger: log.NewNopLogger(),
+	}, Arguments{})
+	require.NoError(t, err)
+	require.NotNil(t, comp)
+
+	ctx, cancel := context.WithTimeout(ctx, time.Second)
+	defer cancel()
+
+	go func() {
+		err := comp.Run(ctx)
+		require.NoError(t, err)
+	}()
+
+	time.Sleep(100 * time.Millisecond)
+}
+
+func TestComponent_ExportsReceiver(t *testing.T) {
+	var exports component.Exports
+
+	comp, err := New(component.Options{
+		ID:     "test",
+		Logger: log.NewNopLogger(),
+		OnStateChange: func(e component.Exports) {
+			exports = e
+		},
+	}, Arguments{})
+	require.NoError(t, err)
+	require.NotNil(t, comp)
+
+	echoExports, ok := exports.(Exports)
+	require.True(t, ok)
+	require.NotNil(t, echoExports.Receiver)
+
+	require.Equal(t, comp, echoExports.Receiver)
+}
+
+func TestAppender_BasicMetrics(t *testing.T) {
+	comp, err := New(component.Options{
+		ID:     "test",
+		Logger: log.NewNopLogger(),
+	}, Arguments{})
+	require.NoError(t, err)
+
+	ctx := context.Background()
+	appender := comp.Appender(ctx)
+	require.NotNil(t, appender)
+
+	lbls := labels.FromStrings("__name__", "test_metric", "job", "test")
+
+	ref, err := appender.Append(0, lbls, time.Now().Unix(), 42.0)
+	require.NoError(t, err)
+	require.NotEqual(t, storage.SeriesRef(0), ref)
+
+	err = appender.Commit()
+	require.NoError(t, err)
+}
+
+func TestAppender_Rollback(t *testing.T) {
+	comp, err := New(component.Options{
+		ID:     "test",
+		Logger: log.NewNopLogger(),
+	}, Arguments{})
+	require.NoError(t, err)
+
+	ctx := context.Background()
+	appender := comp.Appender(ctx)
+	require.NotNil(t, appender)
+
+	lbls := labels.FromStrings("__name__", "test_metric", "job", "test")
+
+	_, err = appender.Append(0, lbls, time.Now().Unix(), 42.0)
+	require.NoError(t, err)
+
+	err = appender.Rollback()
+	require.NoError(t, err)
+}
+
+func TestAppender_MultipleMetrics(t *testing.T) {
+	comp, err := New(component.Options{
+		ID:     "test",
+		Logger: log.NewNopLogger(),
+	}, Arguments{})
+	require.NoError(t, err)
+
+	ctx := context.Background()
+	appender := comp.Appender(ctx)
+	require.NotNil(t, appender)
+
+	metrics := []struct {
+		name  string
+		value float64
+	}{
+		{"metric_one", 1.0},
+		{"metric_two", 2.0},
+		{"metric_three", 3.0},
+	}
+
+	for _, metric := range metrics {
+		lbls := labels.FromStrings("__name__", metric.name, "job", "test")
+		_, err = appender.Append(0, lbls, time.Now().Unix(), metric.value)
+		require.NoError(t, err)
+	}
+
+	err = appender.Commit()
+	require.NoError(t, err)
+}
+
+func TestComponent_Update(t *testing.T) {
+	comp, err := New(component.Options{
+		ID:     "test",
+		Logger: log.NewNopLogger(),
+	}, Arguments{})
+	require.NoError(t, err)
+
+	err = comp.Update(Arguments{})
+	require.NoError(t, err)
+}
+
+func TestAppender_WithExpfmtEncoding(t *testing.T) {
+	var loggedOutput string
+
+	logger := log.LoggerFunc(func(keyvals ...interface{}) error {
+		for i := 0; i < len(keyvals); i += 2 {
+			if keyvals[i] == "metrics" && i+1 < len(keyvals) {
+				loggedOutput = keyvals[i+1].(string)
+			}
+		}
+		return nil
+	})
+
+	comp, err := New(component.Options{
+		ID:     "test",
+		Logger: logger,
+	}, Arguments{})
+	require.NoError(t, err)
+
+	ctx := context.Background()
+	appender := comp.Appender(ctx)
+
+	lbls := labels.FromStrings("__name__", "test_metric", "job", "test_job", "instance", "localhost:8080")
+	_, err = appender.Append(0, lbls, time.Now().Unix(), 42.0)
+	require.NoError(t, err)
+
+	err = appender.Commit()
+	require.NoError(t, err)
+
+	require.NotEmpty(t, loggedOutput)
+	require.Contains(t, loggedOutput, "test_metric")
+	require.Contains(t, loggedOutput, "job=\"test_job\"")
+	require.Contains(t, loggedOutput, "instance=\"localhost:8080\"")
+	require.Contains(t, loggedOutput, "42")
+
+	require.NotContains(t, loggedOutput, "Prometheus metrics received by")
+	require.NotContains(t, loggedOutput, "Timestamp:")
+}
+
+func TestAppender_WithOpenMetricsFormat(t *testing.T) {
+	var loggedOutput string
+
+	logger := log.LoggerFunc(func(keyvals ...interface{}) error {
+		for i := 0; i < len(keyvals); i += 2 {
+			if keyvals[i] == "metrics" && i+1 < len(keyvals) {
+				loggedOutput = keyvals[i+1].(string)
+			}
+		}
+		return nil
+	})
+
+	args := Arguments{Format: "openmetrics"}
+
+	comp, err := New(component.Options{
+		ID:     "test",
+		Logger: logger,
+	}, args)
+	require.NoError(t, err)
+
+	ctx := context.Background()
+	appender := comp.Appender(ctx)
+
+	lbls := labels.FromStrings("__name__", "test_metric", "job", "test_job")
+	_, err = appender.Append(0, lbls, time.Now().Unix(), 42.0)
+	require.NoError(t, err)
+
+	err = appender.Commit()
+	require.NoError(t, err)
+
+	require.NotEmpty(t, loggedOutput)
+	require.Contains(t, loggedOutput, "test_metric")
+	require.Contains(t, loggedOutput, "job=\"test_job\"")
+
+	t.Logf("OpenMetrics output: %s", loggedOutput)
+}
+
+func TestArguments_Defaults(t *testing.T) {
+	args := Arguments{}
+	args.SetToDefault()
+
+	require.Equal(t, "text", args.Format)
+}