diff --git a/cmd/promtool/main.go b/cmd/promtool/main.go
index 0304fa2d57..c6a5801d28 100644
--- a/cmd/promtool/main.go
+++ b/cmd/promtool/main.go
@@ -257,15 +257,15 @@ func main() {
 	tsdbDumpCmd := tsdbCmd.Command("dump", "Dump samples from a TSDB.")
 	dumpPath := tsdbDumpCmd.Arg("db path", "Database path (default is "+defaultDBPath+").").Default(defaultDBPath).String()
 	dumpSandboxDirRoot := tsdbDumpCmd.Flag("sandbox-dir-root", "Root directory where a sandbox directory will be created, this sandbox is used in case WAL replay generates chunks (default is the database path). The sandbox is cleaned up at the end.").String()
-	dumpMinTime := tsdbDumpCmd.Flag("min-time", "Minimum timestamp to dump.").Default(strconv.FormatInt(math.MinInt64, 10)).Int64()
-	dumpMaxTime := tsdbDumpCmd.Flag("max-time", "Maximum timestamp to dump.").Default(strconv.FormatInt(math.MaxInt64, 10)).Int64()
+	dumpMinTime := tsdbDumpCmd.Flag("min-time", "Minimum timestamp to dump, in milliseconds since the Unix epoch.").Default(strconv.FormatInt(math.MinInt64, 10)).Int64()
+	dumpMaxTime := tsdbDumpCmd.Flag("max-time", "Maximum timestamp to dump, in milliseconds since the Unix epoch.").Default(strconv.FormatInt(math.MaxInt64, 10)).Int64()
 	dumpMatch := tsdbDumpCmd.Flag("match", "Series selector. Can be specified multiple times.").Default("{__name__=~'(?s:.*)'}").Strings()
 
 	tsdbDumpOpenMetricsCmd := tsdbCmd.Command("dump-openmetrics", "[Experimental] Dump samples from a TSDB into OpenMetrics text format, excluding native histograms and staleness markers, which are not representable in OpenMetrics.")
 	dumpOpenMetricsPath := tsdbDumpOpenMetricsCmd.Arg("db path", "Database path (default is "+defaultDBPath+").").Default(defaultDBPath).String()
 	dumpOpenMetricsSandboxDirRoot := tsdbDumpOpenMetricsCmd.Flag("sandbox-dir-root", "Root directory where a sandbox directory will be created, this sandbox is used in case WAL replay generates chunks (default is the database path). The sandbox is cleaned up at the end.").String()
-	dumpOpenMetricsMinTime := tsdbDumpOpenMetricsCmd.Flag("min-time", "Minimum timestamp to dump.").Default(strconv.FormatInt(math.MinInt64, 10)).Int64()
-	dumpOpenMetricsMaxTime := tsdbDumpOpenMetricsCmd.Flag("max-time", "Maximum timestamp to dump.").Default(strconv.FormatInt(math.MaxInt64, 10)).Int64()
+	dumpOpenMetricsMinTime := tsdbDumpOpenMetricsCmd.Flag("min-time", "Minimum timestamp to dump, in milliseconds since the Unix epoch.").Default(strconv.FormatInt(math.MinInt64, 10)).Int64()
+	dumpOpenMetricsMaxTime := tsdbDumpOpenMetricsCmd.Flag("max-time", "Maximum timestamp to dump, in milliseconds since the Unix epoch.").Default(strconv.FormatInt(math.MaxInt64, 10)).Int64()
 	dumpOpenMetricsMatch := tsdbDumpOpenMetricsCmd.Flag("match", "Series selector. Can be specified multiple times.").Default("{__name__=~'(?s:.*)'}").Strings()
 
 	importCmd := tsdbCmd.Command("create-blocks-from", "[Experimental] Import samples from input and produce TSDB blocks. Please refer to the storage docs for more details.")
diff --git a/docs/command-line/promtool.md b/docs/command-line/promtool.md
index 1c4c0a18f9..3b1ca84f6b 100644
--- a/docs/command-line/promtool.md
+++ b/docs/command-line/promtool.md
@@ -581,8 +581,8 @@ Dump samples from a TSDB.
 | Flag | Description | Default |
 | --- | --- | --- |
 | <code class="text-nowrap">--sandbox-dir-root</code> | Root directory where a sandbox directory will be created, this sandbox is used in case WAL replay generates chunks (default is the database path). The sandbox is cleaned up at the end. |  |
-| <code class="text-nowrap">--min-time</code> | Minimum timestamp to dump. | `-9223372036854775808` |
-| <code class="text-nowrap">--max-time</code> | Maximum timestamp to dump. | `9223372036854775807` |
+| <code class="text-nowrap">--min-time</code> | Minimum timestamp to dump, in milliseconds since the Unix epoch. | `-9223372036854775808` |
+| <code class="text-nowrap">--max-time</code> | Maximum timestamp to dump, in milliseconds since the Unix epoch. | `9223372036854775807` |
 | <code class="text-nowrap">--match</code> <code class="text-nowrap">...<code class="text-nowrap"> | Series selector. Can be specified multiple times. | `{__name__=~'(?s:.*)'}` |
 
 
@@ -608,8 +608,8 @@ Dump samples from a TSDB.
 | Flag | Description | Default |
 | --- | --- | --- |
 | <code class="text-nowrap">--sandbox-dir-root</code> | Root directory where a sandbox directory will be created, this sandbox is used in case WAL replay generates chunks (default is the database path). The sandbox is cleaned up at the end. |  |
-| <code class="text-nowrap">--min-time</code> | Minimum timestamp to dump. | `-9223372036854775808` |
-| <code class="text-nowrap">--max-time</code> | Maximum timestamp to dump. | `9223372036854775807` |
+| <code class="text-nowrap">--min-time</code> | Minimum timestamp to dump, in milliseconds since the Unix epoch. | `-9223372036854775808` |
+| <code class="text-nowrap">--max-time</code> | Maximum timestamp to dump, in milliseconds since the Unix epoch. | `9223372036854775807` |
 | <code class="text-nowrap">--match</code> <code class="text-nowrap">...<code class="text-nowrap"> | Series selector. Can be specified multiple times. | `{__name__=~'(?s:.*)'}` |