diff --git a/client/src/components/datetime-picker.tsx b/client/src/components/datetime-picker.tsx
new file mode 100644
index 0000000..9f1f009
--- /dev/null
+++ b/client/src/components/datetime-picker.tsx
@@ -0,0 +1,210 @@
+import { useState, useEffect } from "react";
+import { Calendar } from "@/components/ui/calendar";
+import { Popover, PopoverContent, PopoverTrigger } from "@/components/ui/popover";
+import { Button } from "@/components/ui/button";
+import { Calendar as CalendarIcon, Clock, X } from "lucide-react";
+import { format } from "date-fns";
+import { fr } from "date-fns/locale";
+import { cn } from "@/lib/utils";
+import { ScrollArea } from "@/components/ui/scroll-area";
+
+interface DateTimePickerProps {
+  value: Date | undefined;
+  onChange: (date: Date | undefined) => void;
+  occupiedDates?: Date[];
+  placeholder?: string;
+}
+
+const OPTIMAL_HOURS = [8, 12, 13, 18, 19, 20];
+
+export function DateTimePicker({ value, onChange, occupiedDates = [], placeholder = "Sélectionner une date" }: DateTimePickerProps) {
+  const [selectedDate, setSelectedDate] = useState<Date | undefined>(value);
+  const [selectedHour, setSelectedHour] = useState<number>(value?.getHours() || 8);
+  const [selectedMinute, setSelectedMinute] = useState<number>(value?.getMinutes() || 0);
+
+  // Sync internal state with parent value prop
+  useEffect(() => {
+    if (value) {
+      setSelectedDate(value);
+      setSelectedHour(value.getHours());
+      setSelectedMinute(value.getMinutes());
+    } else {
+      setSelectedDate(undefined);
+      setSelectedHour(8);
+      setSelectedMinute(0);
+    }
+  }, [value]);
+
+  const hours = Array.from({ length: 24 }, (_, i) => i);
+  const minutes = [0, 15, 30, 45];
+
+  const isOptimalHour = (hour: number) => OPTIMAL_HOURS.includes(hour);
+
+  const handleDateSelect = (date: Date | undefined) => {
+    setSelectedDate(date);
+    if (date) {
+      const newDate = new Date(date);
+      newDate.setHours(selectedHour);
+      newDate.setMinutes(selectedMinute);
+      onChange(newDate);
+    } else {
+      onChange(undefined);
+    }
+  };
+
+  const handleTimeChange = (hour: number, minute: number) => {
+    setSelectedHour(hour);
+    setSelectedMinute(minute);
+    if (selectedDate) {
+      const newDate = new Date(selectedDate);
+      newDate.setHours(hour);
+      newDate.setMinutes(minute);
+      onChange(newDate);
+    }
+  };
+
+  // Convert occupied dates to a Set of date strings for efficient lookup
+  const occupiedDateStrings = new Set(
+    occupiedDates.map(date => format(date, 'yyyy-MM-dd'))
+  );
+
+  // Check if a date is occupied
+  const isDateOccupied = (date: Date) => {
+    return occupiedDateStrings.has(format(date, 'yyyy-MM-dd'));
+  };
+
+  return (
+    <div className="space-y-3">
+      <div className="flex gap-2">
+        <Popover>
+          <PopoverTrigger asChild>
+            <Button
+              variant="outline"
+              className={cn(
+                "flex-1 justify-start text-left font-normal",
+                !value && "text-muted-foreground"
+              )}
+              data-testid="button-date-picker"
+            >
+              <CalendarIcon className="mr-2 h-4 w-4" />
+              {value ? format(value, "PPP", { locale: fr }) : <span>{placeholder}</span>}
+            </Button>
+          </PopoverTrigger>
+          <PopoverContent className="w-auto p-0" align="start">
+            <Calendar
+              mode="single"
+              selected={selectedDate}
+              onSelect={handleDateSelect}
+              locale={fr}
+              modifiers={{
+                occupied: (date) => isDateOccupied(date)
+              }}
+              modifiersClassNames={{
+                occupied: "bg-red-500/20 text-red-700 dark:text-red-300 font-bold hover:bg-red-500/30"
+              }}
+              disabled={(date) => date < new Date(new Date().setHours(0, 0, 0, 0))}
+              data-testid="calendar-picker"
+            />
+          </PopoverContent>
+        </Popover>
+        {value && (
+          <Button
+            variant="outline"
+            size="icon"
+            onClick={() => {
+              setSelectedDate(undefined);
+              onChange(undefined);
+            }}
+            className="shrink-0"
+            data-testid="button-clear-date"
+          >
+            <X className="h-4 w-4" />
+          </Button>
+        )}
+      </div>
+
+      {selectedDate && (
+        <Popover>
+          <PopoverTrigger asChild>
+            <Button
+              variant="outline"
+              className="w-full justify-start text-left font-normal"
+              data-testid="button-time-picker"
+            >
+              <Clock className="mr-2 h-4 w-4" />
+              {String(selectedHour).padStart(2, '0')}:{String(selectedMinute).padStart(2, '0')}
+            </Button>
+          </PopoverTrigger>
+          <PopoverContent className="w-auto p-0" align="start">
+            <div className="flex">
+              <ScrollArea className="h-60">
+                <div className="p-2">
+                  <div className="text-xs font-semibold mb-2 px-2 text-muted-foreground">Heures</div>
+                  {hours.map((hour) => (
+                    <Button
+                      key={hour}
+                      variant="ghost"
+                      className={cn(
+                        "w-full justify-center mb-1",
+                        selectedHour === hour && "bg-primary text-primary-foreground",
+                        isOptimalHour(hour) && selectedHour !== hour && "bg-green-500/20 text-green-700 dark:text-green-300 font-semibold hover:bg-green-500/30"
+                      )}
+                      onClick={() => handleTimeChange(hour, selectedMinute)}
+                      data-testid={`hour-${hour}`}
+                    >
+                      {String(hour).padStart(2, '0')}h
+                      {isOptimalHour(hour) && selectedHour !== hour && (
+                        <span className="ml-1 text-[10px]">✨</span>
+                      )}
+                    </Button>
+                  ))}
+                </div>
+              </ScrollArea>
+              <ScrollArea className="h-60 border-l">
+                <div className="p-2">
+                  <div className="text-xs font-semibold mb-2 px-2 text-muted-foreground">Minutes</div>
+                  {minutes.map((minute) => (
+                    <Button
+                      key={minute}
+                      variant="ghost"
+                      className={cn(
+                        "w-full justify-center mb-1",
+                        selectedMinute === minute && "bg-primary text-primary-foreground"
+                      )}
+                      onClick={() => handleTimeChange(selectedHour, minute)}
+                      data-testid={`minute-${minute}`}
+                    >
+                      {String(minute).padStart(2, '0')}
+                    </Button>
+                  ))}
+                </div>
+              </ScrollArea>
+            </div>
+            <div className="p-3 border-t bg-muted/50">
+              <div className="flex items-center gap-2 mb-1">
+                <div className="w-2 h-2 rounded-full bg-green-500"></div>
+                <span className="text-[10px] font-semibold text-green-600 dark:text-green-400">
+                  Heures optimales (8h, 12h-13h, 18h-20h)
+                </span>
+              </div>
+              <p className="text-[9px] text-muted-foreground">
+                Ces créneaux maximisent l'engagement
+              </p>
+            </div>
+          </PopoverContent>
+        </Popover>
+      )}
+
+      {occupiedDates.length > 0 && (
+        <div className="p-3 bg-red-500/10 rounded-lg border border-red-500/20">
+          <div className="flex items-center gap-2">
+            <div className="w-2 h-2 rounded-full bg-red-500"></div>
+            <span className="text-xs font-semibold text-red-600 dark:text-red-400">
+              Les dates en fond rouge ont déjà des publications programmées
+            </span>
+          </div>
+        </div>
+      )}
+    </div>
+  );
+}
diff --git a/client/src/pages/new-post.tsx b/client/src/pages/new-post.tsx
index 7a1cdb2..d817c7c 100644
--- a/client/src/pages/new-post.tsx
+++ b/client/src/pages/new-post.tsx
@@ -34,6 +34,7 @@ import { useToast } from "@/hooks/use-toast";
 import { apiRequest, queryClient } from "@/lib/queryClient";
 import type { SocialPage, Media, ScheduledPost } from "@shared/schema";
 import { PreviewModal } from "@/components/preview-modal";
+import { DateTimePicker } from "@/components/datetime-picker";
 
 function SortableMediaItem({ 
   media, 
@@ -108,7 +109,7 @@ export default function NewPost() {
   const [productInfo, setProductInfo] = useState('');
   const [selectedMedia, setSelectedMedia] = useState<string[]>([]);
   const [selectedPages, setSelectedPages] = useState<string[]>([]);
-  const [scheduledDate, setScheduledDate] = useState('');
+  const [scheduledDate, setScheduledDate] = useState<Date | undefined>(undefined);
   const [generatedVariants, setGeneratedVariants] = useState<any[]>([]);
   const [postText, setPostText] = useState('');
   const [postType, setPostType] = useState<'feed' | 'story' | 'both'>('feed');
@@ -280,7 +281,7 @@ export default function NewPost() {
 
     createPostMutation.mutate({
       content: postText,
-      scheduledFor: scheduledDate ? new Date(scheduledDate).toISOString() : undefined,
+      scheduledFor: scheduledDate ? scheduledDate.toISOString() : undefined,
       mediaIds: selectedMedia.length > 0 ? selectedMedia : undefined,
       pageIds: selectedPages,
       postType,
@@ -712,91 +713,18 @@ export default function NewPost() {
                 </CardHeader>
                 <CardContent>
                   <div className="space-y-3">
-                    <Label htmlFor="scheduledDate">Date et heure</Label>
-                    <Input
-                      id="scheduledDate"
-                      type="datetime-local"
+                    <Label>Date et heure</Label>
+                    <DateTimePicker
                       value={scheduledDate}
-                      onChange={(e) => setScheduledDate(e.target.value)}
-                      data-testid="input-scheduled-date"
+                      onChange={setScheduledDate}
+                      occupiedDates={scheduledPosts
+                        .filter(post => post.scheduledAt)
+                        .map(post => new Date(post.scheduledAt!))}
+                      placeholder="Publier immédiatement"
                     />
                     <p className="text-xs text-muted-foreground">
-                      Laissez vide pour publier immédiatement
+                      Sélectionnez une date pour planifier, sinon publication immédiate
                     </p>
-                    
-                    {(() => {
-                      // Get dates with scheduled posts
-                      const datesWithPosts = scheduledPosts
-                        .filter(post => post.scheduledAt)
-                        .map(post => {
-                          const date = new Date(post.scheduledAt!);
-                          return date.toISOString().split('T')[0];
-                        })
-                        .filter((date, index, self) => self.indexOf(date) === index)
-                        .sort();
-                      
-                      if (datesWithPosts.length > 0) {
-                        return (
-                          <div className="p-3 bg-red-500/10 rounded-lg border border-red-500/20">
-                            <div className="flex items-center gap-2 mb-2">
-                              <div className="w-2 h-2 rounded-full bg-red-500"></div>
-                              <span className="text-xs font-semibold text-red-600 dark:text-red-400">
-                                Dates avec publications programmées
-                              </span>
-                            </div>
-                            <div className="flex flex-wrap gap-2">
-                              {datesWithPosts.slice(0, 5).map((date) => {
-                                const dateObj = new Date(date + 'T00:00:00');
-                                const formatted = dateObj.toLocaleDateString('fr-FR', { 
-                                  day: '2-digit', 
-                                  month: 'short' 
-                                });
-                                return (
-                                  <span 
-                                    key={date} 
-                                    className="text-xs px-2 py-1 bg-red-500/20 text-red-700 dark:text-red-300 rounded-md font-medium"
-                                  >
-                                    {formatted}
-                                  </span>
-                                );
-                              })}
-                              {datesWithPosts.length > 5 && (
-                                <span className="text-xs px-2 py-1 text-red-600 dark:text-red-400 font-medium">
-                                  +{datesWithPosts.length - 5} autre{datesWithPosts.length - 5 > 1 ? 's' : ''}
-                                </span>
-                              )}
-                            </div>
-                            <p className="text-[10px] text-red-600/80 dark:text-red-400/80 mt-2">
-                              Ces dates ont déjà des publications planifiées
-                            </p>
-                          </div>
-                        );
-                      }
-                      return null;
-                    })()}
-                    
-                    <div className="p-3 bg-green-500/10 rounded-lg border border-green-500/20">
-                      <div className="flex items-center gap-2 mb-2">
-                        <div className="w-2 h-2 rounded-full bg-green-500"></div>
-                        <span className="text-xs font-semibold text-green-600 dark:text-green-400">
-                          Heures optimales pour l'audience
-                        </span>
-                      </div>
-                      <div className="flex flex-wrap gap-2">
-                        <span className="text-xs px-2 py-1 bg-green-500/20 text-green-700 dark:text-green-300 rounded-md font-medium">
-                          8h - 9h
-                        </span>
-                        <span className="text-xs px-2 py-1 bg-green-500/20 text-green-700 dark:text-green-300 rounded-md font-medium">
-                          12h - 14h
-                        </span>
-                        <span className="text-xs px-2 py-1 bg-green-500/20 text-green-700 dark:text-green-300 rounded-md font-medium">
-                          18h - 21h
-                        </span>
-                      </div>
-                      <p className="text-[10px] text-green-600/80 dark:text-green-400/80 mt-2">
-                        Ces créneaux maximisent la portée de vos publications
-                      </p>
-                    </div>
                   </div>
                 </CardContent>
               </Card>