diff --git a/ha-thermostat-calibration.yaml b/ha-thermostat-calibration.yaml
new file mode 100644
index 0000000..794a570
--- /dev/null
+++ b/ha-thermostat-calibration.yaml
@@ -0,0 +1,179 @@
+blueprint:
+  name: Area Valve Temperature Offset Calibration
+  author: Andreas Gammelgaard Damsbo
+  description: |
+    Automatically calibrate the temperature offset of ALL smart radiator valves (TRVs)
+    in a specified area using readings from an external room temperature sensor.
+    
+    The blueprint discovers all climate entities in the chosen area and updates their
+    corresponding temperature offset entities based on the difference between each
+    valve's internal sensor and the actual room temperature.
+    
+    ⚙️ Example use case:
+      - **area**: Living Room
+      - **external_sensor**: sensor.living_room_temperature
+      - **rounding_step**: 1.0
+      
+    The blueprint will find all thermostats in "Living Room" and calibrate each one
+    to match the external sensor reading. Thermostats without offset entities are
+    automatically skipped.
+    
+    ➕ Manual correction:
+      Use the **manual_correction** slider to bias the calculated offset in cases where
+      valves tend to stop heating too early or overheat even after calibration.
+      
+      - Positive value (e.g., +0.3 °C): Valves assume room is warmer → reduce heating sooner
+      - Negative value (e.g., −0.3 °C): Valves assume room is cooler → prolong heating
+
+  domain: automation
+  source_url: 
+
+  input:
+    target_area:
+      name: Area
+      description: >
+        Select the area containing the thermostatic valves you want to calibrate.
+        All climate entities in this area will be automatically calibrated using
+        the external temperature sensor.
+      selector:
+        area: {}
+
+    external_sensor:
+      name: External temperature sensor
+      description: >
+        Select the temperature sensor that measures the actual room temperature
+        for this area. This should be a reliable sensor that provides accurate
+        ambient temperature readings.
+        Example: sensor.living_room_temperature
+      selector:
+        entity:
+          domain: sensor
+          device_class: temperature
+
+    min_interval:
+      name: Minimum time between updates
+      description: >
+        The minimum amount of time (in seconds) that must pass before offsets
+        can be updated again. This prevents valves from being recalibrated too often.
+        A typical value is 300 seconds (5 minutes).
+      default: 300
+      selector:
+        number:
+          min: 30
+          max: 3600
+          step: 1
+          mode: box
+          unit_of_measurement: s
+
+    rounding_step:
+      name: Rounding step for offset value
+      description: >
+        Define the step to which calculated offsets should be rounded.
+        Use 0.5 for valves that support half-degree steps, or 1.0 for full degrees.
+      default: 1.0
+      selector:
+        number:
+          min: 0.1
+          max: 2
+          step: 0.1
+          mode: box
+          unit_of_measurement: "°C"
+
+    manual_correction:
+      name: Manual correction (bias)
+      description: >
+        Additional manual bias applied to computed offsets **before rounding**.
+        Use this if valves still behave undesirably after calibration:
+        - **Positive value** (e.g., +0.1…+1.0 °C): Makes valves think it's **warmer** → **reduces** heating sooner
+        - **Negative value** (e.g., −0.1…−1.0 °C): Makes valves think it's **cooler** → **prolongs** heating
+        Recommended start: 0.0 °C. Adjust in small steps (±0.1 °C) and observe behavior.
+      default: 0.0
+      selector:
+        number:
+          min: -1.0
+          max: 1.0
+          step: 0.1
+          mode: slider
+          unit_of_measurement: "°C"
+
+    offset_entity_suffix:
+      name: Offset entity suffix pattern
+      description: >
+        The text pattern used to identify offset number entities.
+        By default, looks for entities containing "temperature_offset" or "local_temperature_offset".
+        Only change this if your devices use a different naming pattern.
+      default: "temperature_offset"
+      selector:
+        text: {}
+
+mode: queued
+max: 10
+max_exceeded: silent
+
+trigger:
+  - platform: state
+    entity_id: !input external_sensor
+  - platform: state
+    entity_id: climate.*
+    attribute: current_temperature
+
+action:
+  # Rate limiting check
+  - condition: template
+    value_template: >
+      {% set last = state_attr(this.entity_id, 'last_triggered') %}
+      {{ last is none or (as_timestamp(now()) - as_timestamp(last)) > min_interval }}
+  
+  # Process each climate entity in the area
+  - repeat:
+      for_each: >
+        {{ area_entities(target_area) | select('match', '^climate\.') | list }}
+      sequence:
+        - variables:
+            climate_entity: "{{ repeat.item }}"
+            climate_device: "{{ device_id(climate_entity) }}"
+            external_temp: "{{ states(external_sensor) | float(0) }}"
+            valve_temp: "{{ state_attr(climate_entity, 'current_temperature') | float(0) }}"
+        
+        # Skip if climate entity is unavailable or has no valid temperature
+        - condition: template
+          value_template: >
+            {{ states(climate_entity) not in ['unknown', 'unavailable'] and valve_temp > 0 and external_temp > 0 }}
+        
+        # Find offset entity for this device
+        - variables:
+            offset_entity: >
+              {% set entities = device_entities(climate_device) if climate_device else [] %}
+              {% set offset_entities = entities | select('match', '^number\.') | select('search', offset_entity_suffix) | list %}
+              {{ offset_entities[0] if offset_entities else '' }}
+        
+        # Skip if no offset entity found
+        - condition: template
+          value_template: "{{ offset_entity != '' }}"
+        
+        - condition: template
+          value_template: "{{ states(offset_entity) not in ['unknown', 'unavailable'] }}"
+        
+        # Calculate and set new offset
+        - variables:
+            current_offset: "{{ states(offset_entity) | float(0) }}"
+            raw_offset: "{{ external_temp - (valve_temp - current_offset) + manual_correction }}"
+            new_offset: "{{ ((raw_offset / rounding_step) | round(0)) * rounding_step }}"
+        
+        - service: number.set_value
+          target:
+            entity_id: "{{ offset_entity }}"
+          data:
+            value: "{{ new_offset }}"
+        
+        # Small delay between updates to avoid overwhelming the system
+        - delay:
+            milliseconds: 100
+
+variables:
+  target_area: !input target_area
+  external_sensor: !input external_sensor
+  min_interval: !input min_interval
+  rounding_step: !input rounding_step
+  manual_correction: !input manual_correction
+  offset_entity_suffix: !input offset_entity_suffix