diff --git a/src/components/prometheus/queries.ts b/src/components/prometheus/queries.ts
index 557b2b81..108e7adb 100644
--- a/src/components/prometheus/queries.ts
+++ b/src/components/prometheus/queries.ts
@@ -1,4 +1,13 @@
-export type TimeRange = '30s' | '2m' | '5m' | '1h' | '1d';
+type TimeUnit = 'ms' | 's' | 'm' | 'h' | 'd' | 'w' | 'y';
+type UnitDuration = `${bigint}${TimeUnit}`;
+/**
+ * PromQL time duration format. Supports floats in seconds (e.g. '90', '1.5'),
+ * unit suffixes (e.g. '30s', '5m', '1h'), and combined durations (e.g. '1h30m').
+ */
+export type TimeRange =
+  | `${number}`
+  | UnitDuration
+  | `${UnitDuration}${UnitDuration}`;
 
 const metricName = 'http_server_duration_milliseconds';
 const countPostfix = 'count';