diff --git a/app/Http/Controllers/WorkoutSessionController.php b/app/Http/Controllers/WorkoutSessionController.php
index 3b52d11..658018d 100644
--- a/app/Http/Controllers/WorkoutSessionController.php
+++ b/app/Http/Controllers/WorkoutSessionController.php
@@ -3,6 +3,7 @@
 namespace App\Http\Controllers;
 
 use App\Http\Requests\WorkoutSessionsRequest;
+use App\Http\Requests\WorkoutSessionsCalendarRequest;
 use App\Http\Resources\WorkoutSessionsResource;
 use Carbon\CarbonImmutable;
 use Illuminate\Http\JsonResponse;
@@ -32,6 +33,36 @@ class WorkoutSessionController extends Controller
         return WorkoutSessionsResource::collection($workoutSessions);
     }
 
+    public function calendar(WorkoutSessionsCalendarRequest $request): JsonResponse
+    {
+        $month = $request->validated('month') ?? now()->format('Y-m');
+        $referenceDate = CarbonImmutable::createFromFormat('!Y-m', $month);
+        $startDate = $referenceDate->startOfMonth();
+        $endDate = $referenceDate->endOfMonth();
+
+        $days = $request->user()
+            ->workouts()
+            ->whereBetween('started_at', [$startDate->startOfDay(), $endDate->endOfDay()])
+            ->selectRaw('DATE(started_at) as date, COUNT(*) as workouts_count')
+            ->groupByRaw('DATE(started_at)')
+            ->orderBy('date')
+            ->get()
+            ->map(fn ($workoutSession): array => [
+                'date' => CarbonImmutable::parse((string) $workoutSession->date)->toDateString(),
+                'workoutsCount' => (int) $workoutSession->workouts_count,
+            ])
+            ->values();
+
+        return response()->json([
+            'data' => [
+                'month' => $referenceDate->format('Y-m'),
+                'startDate' => $startDate->toDateString(),
+                'endDate' => $endDate->toDateString(),
+                'days' => $days,
+            ],
+        ]);
+    }
+
     public function store(WorkoutSessionsRequest $request): JsonResponse
     {
         $workoutSession = $request->user()
diff --git a/routes/api.php b/routes/api.php
index 3d58163..aa712a6 100644
--- a/routes/api.php
+++ b/routes/api.php
@@ -41,6 +41,7 @@ Route::middleware(['auth:sanctum', 'verified'])->group(function (): void {
 
 // Workouts
 Route::middleware(['auth:sanctum', 'verified'])->group(function (): void {
+    Route::get('workouts/calendar', [WorkoutSessionController::class, 'calendar'])->name('workouts.calendar');
     Route::get('workouts', [WorkoutSessionController::class, 'index'])->name('workouts.index');
     Route::post('workouts', [WorkoutSessionController::class, 'store'])->name('workouts.store');
     Route::get('strava/status', [StravaController::class, 'status'])->name('strava.status');