diff --git a/src/app/api/metrics/activity/route.ts b/src/app/api/metrics/activity/route.ts
index 648696291..7e3bf7ff4 100644
--- a/src/app/api/metrics/activity/route.ts
+++ b/src/app/api/metrics/activity/route.ts
@@ -167,9 +167,9 @@ export async function GET(req: NextRequest) {
   let limit = limitParam ? parseInt(limitParam, 10) : 10;
   let offset = offsetParam ? parseInt(offsetParam, 10) : 0;
 
-  if (isNaN(limit) || limit < 1) limit = 10;
+  if (Number.isNaN(limit) || limit < 1) limit = 10;
   if (limit > 100) limit = 100;
-  if (isNaN(offset) || offset < 0) offset = 0;
+  if (Number.isNaN(offset) || offset < 0) offset = 0;
 
   const bypass = isMetricsCacheBypassed(req);
   const cacheKey = metricsCacheKey(
diff --git a/src/app/api/metrics/contributions/hourly/route.ts b/src/app/api/metrics/contributions/hourly/route.ts
index 6c8740c62..ffdf11c98 100644
--- a/src/app/api/metrics/contributions/hourly/route.ts
+++ b/src/app/api/metrics/contributions/hourly/route.ts
@@ -19,7 +19,7 @@ export async function GET(req: NextRequest) {
 
   const daysParam = req.nextUrl.searchParams.get("days");
   const parsedDays = daysParam ? parseInt(daysParam, 10) : NaN;
-  const days = isNaN(parsedDays) ? 30 : Math.max(1, Math.min(365, parsedDays));
+  const days = Number.isNaN(parsedDays) ? 30 : Math.max(1, Math.min(365, parsedDays));
   const bypass = isMetricsCacheBypassed(req);
   const key = metricsCacheKey(
     session.githubId ?? session.githubLogin,
diff --git a/src/app/api/metrics/contributions/route.ts b/src/app/api/metrics/contributions/route.ts
index 225440241..6c8140444 100644
--- a/src/app/api/metrics/contributions/route.ts
+++ b/src/app/api/metrics/contributions/route.ts
@@ -383,7 +383,7 @@ export async function GET(req: NextRequest) {
   } else {
     const daysParam = req.nextUrl.searchParams.get("days");
     const parsedDays = daysParam ? parseInt(daysParam, 10) : NaN;
-    days = isNaN(parsedDays) ? 30 : Math.max(1, Math.min(365, parsedDays));
+    days = Number.isNaN(parsedDays) ? 30 : Math.max(1, Math.min(365, parsedDays));
   }
 
   const accountId = req.nextUrl.searchParams.get("accountId");
diff --git a/src/app/api/metrics/productive-hours/route.ts b/src/app/api/metrics/productive-hours/route.ts
index 5bb62d383..839a900c4 100644
--- a/src/app/api/metrics/productive-hours/route.ts
+++ b/src/app/api/metrics/productive-hours/route.ts
@@ -223,7 +223,7 @@ export async function GET(req: NextRequest) {
   } else {
     const daysParam = searchParams.get("days");
     const parsedDays = daysParam ? parseInt(daysParam, 10) : NaN;
-    days = isNaN(parsedDays) ? 90 : Math.max(1, Math.min(365, parsedDays));
+    days = Number.isNaN(parsedDays) ? 90 : Math.max(1, Math.min(365, parsedDays));
   }
 
   const accountId = searchParams.get("accountId");
diff --git a/src/app/api/metrics/repos/route.ts b/src/app/api/metrics/repos/route.ts
index 11ef12f67..3d7759da1 100644
--- a/src/app/api/metrics/repos/route.ts
+++ b/src/app/api/metrics/repos/route.ts
@@ -238,7 +238,7 @@ export async function GET(req: NextRequest) {
   const daysParam = req.nextUrl.searchParams.get("days");
   const parsedDays = daysParam ? parseInt(daysParam, 10) : NaN;
   // Clamp days between 1 and 365 — GitHub Commit Search supports up to ~1 year lookback.
-  const days = isNaN(parsedDays) ? 30 : Math.max(1, Math.min(365, parsedDays));
+  const days = Number.isNaN(parsedDays) ? 30 : Math.max(1, Math.min(365, parsedDays));
   const accountId = req.nextUrl.searchParams.get("accountId");
   const bypass = isMetricsCacheBypassed(req);