diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8222b44..e7fe853 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,17 @@ Release notes for each tagged version are extracted from this file by the
 
 ## [Unreleased]
 
+### Added
+- **Operating modes (Auto / Manual).** New `Operating Mode` select switches
+  between the existing temperature-driven curve (**Auto**) and a new **Manual**
+  mode with a `Manual Fan` on/off switch and a `Manual Fan Speed` (0–100 %)
+  number. A single resolved-speed template sensor drives the PWM in both modes,
+  so `Fan Speed` always reflects the actual duty. Safety failsafes (NaN read,
+  >60 s sensor stall → 100 %) still apply in **all** modes, including Manual.
+  Mode + manual controls are grouped on the web UI via `web_server`
+  sorting groups (the stock UI can't hide entities by state, so they are shown
+  but inert in Auto).
+
 ### Changed
 - Home Assistant transport switched from the native ESPHome **`api:` to
   `mqtt:`** in `fancontrol.yaml`. The encrypted native-API block is now
diff --git a/PROJECT_PLAN.md b/PROJECT_PLAN.md
index 9ff0f2a..e8864f9 100644
--- a/PROJECT_PLAN.md
+++ b/PROJECT_PLAN.md
@@ -92,6 +92,21 @@ or the device won't join WiFi.
 components with `restore_value: true` for user-tunable settings. No manual
 NVS wrapping needed.
 
+### F7 — Operating modes
+- **Operating Mode** `select` (`Auto` / `Manual`, persisted). Default `Auto`.
+- **Auto** — unchanged: temperature-driven 5-point fan curve, clamped to Fan Min %.
+- **Manual** — **Manual Fan** `switch` (on/off) + **Manual Fan Speed** `number`
+  (0–100 %). Off forces 0 %.
+- A single template sensor (`fan_speed_pct`) resolves the duty for both modes
+  and drives the PWM output, so "Fan Speed" always reflects the actual duty.
+- **Safety overrides apply in all modes:** NaN sensor read and the >60 s
+  sensor-stall failsafe still force the fan to 100 % even in Manual. The
+  temperature alarm remains indicator-only (does not force the fan).
+- The stock ESPHome web UI cannot hide entities by state, so manual controls
+  are always shown (inert in Auto); `web_server` sorting groups keep them
+  organised. Per-mode conditional UI, if wanted, belongs in a Home Assistant
+  dashboard keyed on the mode entity.
+
 ## 3. Architecture
 
 One file, one responsibility:
diff --git a/README.md b/README.md
index 01256f1..17cb867 100644
--- a/README.md
+++ b/README.md
@@ -74,18 +74,34 @@ broker — no manual entity setup needed. Exposed entities:
 |---|---|---|
 | Temperature | sensor | °C, from DHT22 |
 | Humidity | sensor | %, from DHT22 |
-| Fan Speed | sensor | % duty, derived from the curve |
+| Fan Speed | sensor | % duty actually applied (curve in Auto, manual setting in Manual) |
 | Fan PWM Frequency | sensor | Hz |
 | Restart Counter | sensor | monotonic, persisted in NVS |
 | Uptime | sensor | seconds |
 | WiFi Signal | sensor | dBm |
 | Temperature Alarm | binary_sensor | `safety` class, fires at the configured threshold |
 | Sensor Alarm | binary_sensor | `problem` class, fires after 60 s of no successful reads |
+| Operating Mode | select | `Auto` (curve) or `Manual`, persisted |
+| Manual Fan | switch | on/off — Manual mode only |
+| Manual Fan Speed | number | 0–100 % — Manual mode only |
 | Alarm Temperature | number | tunable threshold |
-| Fan Min % | number | minimum duty under normal operation |
+| Fan Min % | number | minimum duty under normal operation (Auto) |
 | Fan PWM Frequency Setting | number | 1000–5000 Hz, applied live via `ledc.set_frequency` |
 | Restart / Factory Reset | button | standard ESPHome buttons |
 
+## Operating modes
+
+- **Auto** (default) — fan speed follows the temperature curve, clamped to `Fan Min %`.
+- **Manual** — `Manual Fan` toggles the fan and `Manual Fan Speed` sets the duty
+  directly (off forces 0 %).
+
+Safety failsafes apply in **both** modes: a NaN reading or a >60 s sensor stall
+forces the fan to 100 %, even in Manual.
+
+> The built-in ESPHome web page can't hide entities by mode, so the manual
+> controls are always visible (they're simply inert in Auto). For per-mode UI,
+> use a Home Assistant dashboard with conditional cards keyed on `Operating Mode`.
+
 ## Safety behaviour
 
 - **Sensor stall** (no successful DHT22 read for 60 s) → fan forced to 100 %.
diff --git a/fancontrol.yaml b/fancontrol.yaml
index b17dd82..8b46223 100644
--- a/fancontrol.yaml
+++ b/fancontrol.yaml
@@ -91,6 +91,15 @@ mqtt:
 web_server:
   port: 80
   version: 3
+  # The stock web UI cannot hide entities by state, so manual controls are
+  # always visible (they are simply inert in Auto mode). Groups keep it tidy.
+  sorting_groups:
+    - id: group_operation
+      name: "Operation"
+      sorting_weight: 10
+    - id: group_manual
+      name: "Manual control"
+      sorting_weight: 20
 
 # -------- Globals (restore_value = persisted across reboots) --------
 
@@ -127,7 +136,8 @@ sensor:
       filters:
         - filter_out: nan
 
-  # Fan speed derived from the curve. Drives the PWM output via on_value.
+  # Resolved fan speed. Single driver of the PWM output (via on_value) for
+  # BOTH modes, so this sensor always reflects the actual duty being applied.
   - platform: template
     name: "Fan Speed"
     id: fan_speed_pct
@@ -136,9 +146,21 @@ sensor:
     update_interval: 1s
     lambda: |-
       const float t = id(dht_temperature).state;
-      if (std::isnan(t)) return 100.0f;  // sensor warmup / NaN → failsafe bias
-      if (id(alarm_sensor_stall).state) return 100.0f;  // SW watchdog stall
 
+      // Safety overrides apply in ALL modes (Auto and Manual). Preserve these.
+      if (std::isnan(t)) return 100.0f;                 // sensor warmup / NaN → failsafe
+      if (id(alarm_sensor_stall).state) return 100.0f;  // SW watchdog stall → failsafe
+
+      // Manual mode: user-controlled on/off + speed. Off forces 0 %.
+      if (id(operating_mode).state == "Manual") {
+        if (!id(manual_fan_switch).state) return 0.0f;
+        float m = id(manual_fan_speed).state;
+        if (m < 0.0f)   m = 0.0f;
+        if (m > 100.0f) m = 100.0f;
+        return m;
+      }
+
+      // Auto mode: temperature-driven curve (clamped to Fan Min %).
       const float ts[5] = { ${curve_t0}, ${curve_t1}, ${curve_t2}, ${curve_t3}, ${curve_t4} };
       const float ps[5] = { ${curve_p0}, ${curve_p1}, ${curve_p2}, ${curve_p3}, ${curve_p4} };
 
@@ -206,9 +228,60 @@ binary_sensor:
       if (id(last_sensor_read_ms) == 0) return {};
       return (millis() - id(last_sensor_read_ms)) > 60000;
 
+# -------- Operating mode + manual controls --------
+
+select:
+  - platform: template
+    name: "Operating Mode"
+    id: operating_mode
+    icon: mdi:fan-auto
+    web_server:
+      sorting_group_id: group_operation
+    optimistic: true
+    restore_value: true
+    initial_option: "Auto"
+    options:
+      - "Auto"
+      - "Manual"
+    # Recompute the resolved fan speed immediately on mode change.
+    on_value:
+      - component.update: fan_speed_pct
+
+switch:
+  - platform: template
+    name: "Manual Fan"
+    id: manual_fan_switch
+    icon: mdi:fan
+    web_server:
+      sorting_group_id: group_manual
+    optimistic: true
+    restore_mode: RESTORE_DEFAULT_OFF
+    # Only takes effect in Manual mode; inert in Auto.
+    on_turn_on:
+      - component.update: fan_speed_pct
+    on_turn_off:
+      - component.update: fan_speed_pct
+
 # -------- Tunable settings (number components, persisted via restore_value) --------
 
 number:
+  - platform: template
+    name: "Manual Fan Speed"
+    id: manual_fan_speed
+    web_server:
+      sorting_group_id: group_manual
+    min_value: 0
+    max_value: 100
+    step: 1
+    unit_of_measurement: "%"
+    initial_value: 50
+    restore_value: true
+    optimistic: true
+    mode: slider
+    # Only takes effect in Manual mode (with Manual Fan on); inert in Auto.
+    on_value:
+      - component.update: fan_speed_pct
+
   - platform: template
     name: "Alarm Temperature"
     id: alarm_temp_threshold