diff --git a/CODEOWNERS b/CODEOWNERS
index 12aff01e730..e72b1647614 100644
--- a/CODEOWNERS
+++ b/CODEOWNERS
@@ -132,6 +132,7 @@ esphome/components/dashboard_import/* @esphome/core
 esphome/components/datetime/* @jesserockz @rfdarter
 esphome/components/debug/* @esphome/core
 esphome/components/delonghi/* @grob6000
+esphome/components/dew_point/* @CFlix
 esphome/components/dfplayer/* @glmnet
 esphome/components/dfrobot_sen0395/* @niklasweber
 esphome/components/dht/* @OttoWinter
diff --git a/esphome/__main__.py b/esphome/__main__.py
index 0433c09e160..3f0da85a694 100644
--- a/esphome/__main__.py
+++ b/esphome/__main__.py
@@ -92,7 +92,6 @@ _RP2040_UDEV_HINT = (
     "/blob/master/udev/60-picotool.rules"
 )
 
-
 # Special non-component keys that appear in configs
 _NON_COMPONENT_KEYS = frozenset(
     {
@@ -706,12 +705,12 @@ def _make_crystal_freq_callback(
     configured_freq: int,
 ) -> Callable[[str], str | None]:
     """Create a callback that checks esptool crystal frequency output."""
-    crystal_re = re.compile(r"Crystal frequency:\s+(\d+(?:\.\d+)?)\s*MHz")
+    crystal_re = re.compile(r"Crystal frequency:\s+(\d+)\s*MHz")
 
     def check_crystal_line(line: str) -> str | None:
         if not (match := crystal_re.search(line)):
             return None
-        detected = int(float(match.group(1)))
+        detected = int(match.group(1))
         if detected == configured_freq:
             return None
         return (
@@ -724,9 +723,7 @@ def _make_crystal_freq_callback(
             f"  esp32:\n"
             f"    framework:\n"
             f"      sdkconfig_options:\n"
-            f"        CONFIG_XTAL_FREQ_{detected}: 'y'\n"
-            f"        CONFIG_XTAL_FREQ_{configured_freq}: 'n'\n"
-            f'        CONFIG_XTAL_FREQ: "{detected}"\033[0m\n\n'
+            f"        CONFIG_XTAL_FREQ_{detected}: 'y'\033[0m\n\n"
         )
 
     return check_crystal_line
@@ -761,7 +758,11 @@ def upload_using_esptool(
         mcu = get_esp32_variant().lower()
 
     line_callbacks: list[Callable[[str], str | None]] = []
-    if CORE.is_esp32 and (configured_freq := _get_configured_xtal_freq()) is not None:
+    if (
+        CORE.is_esp32
+        and file is None
+        and (configured_freq := _get_configured_xtal_freq()) is not None
+    ):
         line_callbacks.append(_make_crystal_freq_callback(configured_freq))
 
     def run_esptool(baud_rate):
diff --git a/esphome/components/dew_point/__init__.py b/esphome/components/dew_point/__init__.py
new file mode 100644
index 00000000000..3b852436c3c
--- /dev/null
+++ b/esphome/components/dew_point/__init__.py
@@ -0,0 +1 @@
+CODEOWNERS = ["@CFlix"]
diff --git a/esphome/components/dew_point/dew_point.cpp b/esphome/components/dew_point/dew_point.cpp
new file mode 100644
index 00000000000..04ac305e3d2
--- /dev/null
+++ b/esphome/components/dew_point/dew_point.cpp
@@ -0,0 +1,82 @@
+
+#include "dew_point.h"
+
+namespace esphome::dew_point {
+
+static const char *const TAG = "dew_point.sensor";
+
+void DewPointComponent::setup() {
+  // Register callbacks for sensor updates
+  if (this->temperature_sensor_ != nullptr) {
+    this->temperature_sensor_->add_on_state_callback([this](float state) {
+      this->temperature_value_ = state;
+      this->enable_loop();
+    });
+    // Get initial value
+    if (this->temperature_sensor_->has_state()) {
+      this->temperature_value_ = this->temperature_sensor_->get_state();
+    }
+  }
+
+  if (this->humidity_sensor_ != nullptr) {
+    this->humidity_sensor_->add_on_state_callback([this](float state) {
+      this->humidity_value_ = state;
+      this->enable_loop();
+    });
+    // Get initial value
+    if (this->humidity_sensor_->has_state()) {
+      this->humidity_value_ = this->humidity_sensor_->get_state();
+    }
+  }
+}
+
+void DewPointComponent::dump_config() {
+  LOG_SENSOR("", "Dew Point", this);
+  ESP_LOGCONFIG(TAG,
+                "Sources\n"
+                "  Temperature: '%s'\n"
+                "  Humidity: '%s'",
+                this->temperature_sensor_->get_name().c_str(), this->humidity_sensor_->get_name().c_str());
+}
+
+float DewPointComponent::get_setup_priority() const { return setup_priority::DATA; }
+
+void DewPointComponent::loop() {
+  // Only run once
+  this->disable_loop();
+
+  // Check if we have valid values for both sensors
+  if (std::isnan(this->temperature_value_) || std::isnan(this->humidity_value_)) {
+    ESP_LOGW(TAG, "Temperature or humidity value is NaN, skipping calculation");
+    this->publish_state(NAN);
+    return;
+  }
+
+  // Check for valid humidity range
+  if (this->humidity_value_ <= 0.0f || this->humidity_value_ > 100.0f) {
+    ESP_LOGW(TAG, "Humidity value out of range (0-100): %.2f", this->humidity_value_);
+    this->publish_state(NAN);
+    return;
+  }
+
+  // Magnus formula constants
+  const float a{17.625f};
+  const float b{243.04f};
+
+  // Calculate dew point using Magnus formula
+  // Td = (b * alpha) / (a - alpha)
+  // where alpha = ln(RH/100) + (a * T) / (b + T)
+
+  const float alpha{std::log(this->humidity_value_ / 100.0f) +
+                    (a * this->temperature_value_) / (b + this->temperature_value_)};
+
+  const float dew_point{(b * alpha) / (a - alpha)};
+
+  // Publish the calculated dew point
+  this->publish_state(dew_point);
+
+  ESP_LOGD(TAG, "'%s' >> %.1f°C (T: %.1f°C, RH: %.1f%%)", this->get_name().c_str(), dew_point, this->temperature_value_,
+           this->humidity_value_);
+}
+
+}  // namespace esphome::dew_point
diff --git a/esphome/components/dew_point/dew_point.h b/esphome/components/dew_point/dew_point.h
new file mode 100644
index 00000000000..833c50fba25
--- /dev/null
+++ b/esphome/components/dew_point/dew_point.h
@@ -0,0 +1,26 @@
+#pragma once
+
+#include "esphome/core/component.h"
+#include "esphome/components/sensor/sensor.h"
+
+namespace esphome::dew_point {
+
+class DewPointComponent : public Component, public sensor::Sensor {
+ public:
+  void set_temperature_sensor(sensor::Sensor *temperature_sensor) { this->temperature_sensor_ = temperature_sensor; }
+  void set_humidity_sensor(sensor::Sensor *humidity_sensor) { this->humidity_sensor_ = humidity_sensor; }
+
+  void setup() override;
+  void dump_config() override;
+  void loop() override;
+
+  float get_setup_priority() const override;
+
+ protected:
+  sensor::Sensor *temperature_sensor_{nullptr};
+  sensor::Sensor *humidity_sensor_{nullptr};
+  float temperature_value_{NAN};
+  float humidity_value_{NAN};
+};
+
+}  // namespace esphome::dew_point
diff --git a/esphome/components/dew_point/sensor.py b/esphome/components/dew_point/sensor.py
new file mode 100644
index 00000000000..4fee0956021
--- /dev/null
+++ b/esphome/components/dew_point/sensor.py
@@ -0,0 +1,46 @@
+import esphome.codegen as cg
+from esphome.components import sensor
+import esphome.config_validation as cv
+from esphome.const import (
+    CONF_HUMIDITY,
+    CONF_TEMPERATURE,
+    DEVICE_CLASS_TEMPERATURE,
+    STATE_CLASS_MEASUREMENT,
+    UNIT_CELSIUS,
+)
+
+DEPENDENCIES = ["sensor"]
+
+dew_point_ns = cg.esphome_ns.namespace("dew_point")
+DewPointComponent = dew_point_ns.class_(
+    "DewPointComponent", cg.Component, sensor.Sensor
+)
+
+CONFIG_SCHEMA = (
+    sensor.sensor_schema(
+        DewPointComponent,
+        unit_of_measurement=UNIT_CELSIUS,
+        accuracy_decimals=1,
+        device_class=DEVICE_CLASS_TEMPERATURE,
+        state_class=STATE_CLASS_MEASUREMENT,
+        icon="mdi:weather-rainy",
+    )
+    .extend(
+        {
+            cv.Required(CONF_TEMPERATURE): cv.use_id(sensor.Sensor),
+            cv.Required(CONF_HUMIDITY): cv.use_id(sensor.Sensor),
+        }
+    )
+    .extend(cv.COMPONENT_SCHEMA)
+)
+
+
+async def to_code(config):
+    var = await sensor.new_sensor(config)
+    await cg.register_component(var, config)
+
+    temperature_sensor = await cg.get_variable(config[CONF_TEMPERATURE])
+    cg.add(var.set_temperature_sensor(temperature_sensor))
+
+    humidity_sensor = await cg.get_variable(config[CONF_HUMIDITY])
+    cg.add(var.set_humidity_sensor(humidity_sensor))
diff --git a/esphome/components/esp32/gpio.py b/esphome/components/esp32/gpio.py
index c0803f40a83..a7180cbcd7e 100644
--- a/esphome/components/esp32/gpio.py
+++ b/esphome/components/esp32/gpio.py
@@ -88,8 +88,8 @@ def _translate_pin(value):
 
 @dataclass
 class ESP32ValidationFunctions:
-    pin_validation: Callable[[Any], Any]
-    usage_validation: Callable[[Any], Any]
+    pin_validation: Callable[[int], int]
+    usage_validation: Callable[[dict[str, Any]], dict[str, Any]]
 
 
 _esp32_validations = {
diff --git a/esphome/components/esp32/gpio_esp32.py b/esphome/components/esp32/gpio_esp32.py
index 973d2dc0ef3..b3166cf822e 100644
--- a/esphome/components/esp32/gpio_esp32.py
+++ b/esphome/components/esp32/gpio_esp32.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import (
@@ -22,7 +23,7 @@ _ESP32_STRAPPING_PINS = {0, 2, 5, 12, 15}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_validate_gpio_pin(value):
+def esp32_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 39:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-39)")
     if value in _ESP_SDIO_PINS:
@@ -41,7 +42,7 @@ def esp32_validate_gpio_pin(value):
     return value
 
 
-def esp32_validate_supports(value):
+def esp32_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/components/esp32/gpio_esp32_c2.py b/esphome/components/esp32/gpio_esp32_c2.py
index 32a24050ca7..2d6e3a4a4ed 100644
--- a/esphome/components/esp32/gpio_esp32_c2.py
+++ b/esphome/components/esp32/gpio_esp32_c2.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import CONF_INPUT, CONF_MODE, CONF_NUMBER
@@ -9,14 +10,14 @@ _ESP32C2_STRAPPING_PINS = {8, 9}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_c2_validate_gpio_pin(value):
+def esp32_c2_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 20:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-20)")
 
     return value
 
 
-def esp32_c2_validate_supports(value):
+def esp32_c2_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/components/esp32/gpio_esp32_c3.py b/esphome/components/esp32/gpio_esp32_c3.py
index c1427cc02aa..93e0b970934 100644
--- a/esphome/components/esp32/gpio_esp32_c3.py
+++ b/esphome/components/esp32/gpio_esp32_c3.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import CONF_INPUT, CONF_MODE, CONF_NUMBER
@@ -18,7 +19,7 @@ _ESP32C3_STRAPPING_PINS = {2, 8, 9}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_c3_validate_gpio_pin(value):
+def esp32_c3_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 21:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-21)")
     if value in _ESP32C3_SPI_PSRAM_PINS:
@@ -29,7 +30,7 @@ def esp32_c3_validate_gpio_pin(value):
     return value
 
 
-def esp32_c3_validate_supports(value):
+def esp32_c3_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/components/esp32/gpio_esp32_c5.py b/esphome/components/esp32/gpio_esp32_c5.py
index fa2ce1a689c..639ed64c9ea 100644
--- a/esphome/components/esp32/gpio_esp32_c5.py
+++ b/esphome/components/esp32/gpio_esp32_c5.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import CONF_INPUT, CONF_MODE, CONF_NUMBER, CONF_SCL, CONF_SDA
@@ -22,7 +23,7 @@ _ESP32C5_STRAPPING_PINS = {2, 7, 27, 28}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_c5_validate_gpio_pin(value):
+def esp32_c5_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 28:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-28)")
     if value in _ESP32C5_SPI_PSRAM_PINS:
@@ -33,7 +34,7 @@ def esp32_c5_validate_gpio_pin(value):
     return value
 
 
-def esp32_c5_validate_supports(value):
+def esp32_c5_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/components/esp32/gpio_esp32_c6.py b/esphome/components/esp32/gpio_esp32_c6.py
index 5d679dede25..cfd3bca8334 100644
--- a/esphome/components/esp32/gpio_esp32_c6.py
+++ b/esphome/components/esp32/gpio_esp32_c6.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import CONF_INPUT, CONF_MODE, CONF_NUMBER, CONF_SCL, CONF_SDA
@@ -22,7 +23,7 @@ _ESP32C6_STRAPPING_PINS = {8, 9, 15}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_c6_validate_gpio_pin(value):
+def esp32_c6_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 23:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-23)")
     if value in _ESP32C6_SPI_PSRAM_PINS:
@@ -33,7 +34,7 @@ def esp32_c6_validate_gpio_pin(value):
     return value
 
 
-def esp32_c6_validate_supports(value):
+def esp32_c6_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/components/esp32/gpio_esp32_c61.py b/esphome/components/esp32/gpio_esp32_c61.py
index 77be42db3e7..2f3abe6a0f9 100644
--- a/esphome/components/esp32/gpio_esp32_c61.py
+++ b/esphome/components/esp32/gpio_esp32_c61.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import CONF_INPUT, CONF_MODE, CONF_NUMBER
@@ -20,7 +21,7 @@ _ESP32C61_STRAPPING_PINS = {8, 9}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_c61_validate_gpio_pin(value):
+def esp32_c61_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 29:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-29)")
     if value in _ESP32C61_SPI_PSRAM_PINS:
@@ -31,7 +32,7 @@ def esp32_c61_validate_gpio_pin(value):
     return value
 
 
-def esp32_c61_validate_supports(value):
+def esp32_c61_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/components/esp32/gpio_esp32_h2.py b/esphome/components/esp32/gpio_esp32_h2.py
index f37297764b8..5e7a6158f9b 100644
--- a/esphome/components/esp32/gpio_esp32_h2.py
+++ b/esphome/components/esp32/gpio_esp32_h2.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import CONF_INPUT, CONF_MODE, CONF_NUMBER
@@ -13,7 +14,7 @@ _ESP32H2_STRAPPING_PINS = {2, 3, 8, 9, 25}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_h2_validate_gpio_pin(value):
+def esp32_h2_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 27:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-27)")
     if value in _ESP32H2_SPI_FLASH_PINS:
@@ -33,7 +34,7 @@ def esp32_h2_validate_gpio_pin(value):
     return value
 
 
-def esp32_h2_validate_supports(value):
+def esp32_h2_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/components/esp32/gpio_esp32_p4.py b/esphome/components/esp32/gpio_esp32_p4.py
index 2726c5932fa..865db926524 100644
--- a/esphome/components/esp32/gpio_esp32_p4.py
+++ b/esphome/components/esp32/gpio_esp32_p4.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import CONF_INPUT, CONF_MODE, CONF_NUMBER, CONF_SCL, CONF_SDA
@@ -14,7 +15,7 @@ _ESP32P4_STRAPPING_PINS = {34, 35, 36, 37, 38}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_p4_validate_gpio_pin(value):
+def esp32_p4_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 54:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-54)")
     if value in _ESP32P4_USB_JTAG_PINS:
@@ -27,7 +28,7 @@ def esp32_p4_validate_gpio_pin(value):
     return value
 
 
-def esp32_p4_validate_supports(value):
+def esp32_p4_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/components/esp32/gpio_esp32_s2.py b/esphome/components/esp32/gpio_esp32_s2.py
index 331aeb9d94b..4978f48a1c2 100644
--- a/esphome/components/esp32/gpio_esp32_s2.py
+++ b/esphome/components/esp32/gpio_esp32_s2.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import (
@@ -26,7 +27,7 @@ _ESP32S2_STRAPPING_PINS = {0, 45, 46}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_s2_validate_gpio_pin(value):
+def esp32_s2_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 46:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-46)")
 
@@ -43,7 +44,7 @@ def esp32_s2_validate_gpio_pin(value):
     return value
 
 
-def esp32_s2_validate_supports(value):
+def esp32_s2_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/components/esp32/gpio_esp32_s3.py b/esphome/components/esp32/gpio_esp32_s3.py
index aea378f499d..cb0eb8178c3 100644
--- a/esphome/components/esp32/gpio_esp32_s3.py
+++ b/esphome/components/esp32/gpio_esp32_s3.py
@@ -1,4 +1,5 @@
 import logging
+from typing import Any
 
 import esphome.config_validation as cv
 from esphome.const import CONF_INPUT, CONF_MODE, CONF_NUMBER
@@ -27,7 +28,7 @@ _ESP_32S3_STRAPPING_PINS = {0, 3, 45, 46}
 _LOGGER = logging.getLogger(__name__)
 
 
-def esp32_s3_validate_gpio_pin(value):
+def esp32_s3_validate_gpio_pin(value: int) -> int:
     if value < 0 or value > 48:
         raise cv.Invalid(f"Invalid pin number: {value} (must be 0-48)")
 
@@ -49,7 +50,7 @@ def esp32_s3_validate_gpio_pin(value):
     return value
 
 
-def esp32_s3_validate_supports(value):
+def esp32_s3_validate_supports(value: dict[str, Any]) -> dict[str, Any]:
     num = value[CONF_NUMBER]
     mode = value[CONF_MODE]
     is_input = mode[CONF_INPUT]
diff --git a/esphome/util.py b/esphome/util.py
index 754e39afabf..73cc3aa5ab6 100644
--- a/esphome/util.py
+++ b/esphome/util.py
@@ -209,8 +209,8 @@ def run_external_command(
     func,
     *cmd,
     capture_stdout: bool = False,
-    filter_lines: str = None,
-    line_callbacks: list | None = None,
+    filter_lines: list[str] | None = None,
+    line_callbacks: list[Callable[[str], str | None]] | None = None,
 ) -> int | str:
     """
     Run a function from an external package that acts like a main method.
@@ -220,7 +220,9 @@ def run_external_command(
     :param func: Function to execute
     :param cmd: Command to run as (eg first element of sys.argv)
     :param capture_stdout: Capture text from stdout and return that.
-    :param filter_lines: Regular expression used to filter captured output.
+        Note: line_callbacks are not invoked when capture_stdout is True.
+    :param filter_lines: Regular expressions used to filter captured output.
+    :param line_callbacks: Callbacks invoked per line; non-None returns are written to output.
     :return: str if `capture_stdout` is set else int exit code.
 
     """
diff --git a/tests/components/dew_point/common.yaml b/tests/components/dew_point/common.yaml
new file mode 100644
index 00000000000..527eeb2f84b
--- /dev/null
+++ b/tests/components/dew_point/common.yaml
@@ -0,0 +1,19 @@
+sensor:
+  - platform: dew_point
+    name: Dew Point
+    temperature: template_temperature
+    humidity: template_humidity
+  - platform: template
+    id: template_humidity
+    lambda: |-
+      if (millis() > 10000) {
+        return 0.6;
+      }
+      return 0.0;
+  - platform: template
+    id: template_temperature
+    lambda: |-
+      if (millis() > 10000) {
+        return 42.0;
+      }
+      return 0.0;
diff --git a/tests/components/dew_point/test.esp32-idf.yaml b/tests/components/dew_point/test.esp32-idf.yaml
new file mode 100644
index 00000000000..dade44d145b
--- /dev/null
+++ b/tests/components/dew_point/test.esp32-idf.yaml
@@ -0,0 +1 @@
+<<: !include common.yaml
diff --git a/tests/components/dew_point/test.esp8266-ard.yaml b/tests/components/dew_point/test.esp8266-ard.yaml
new file mode 100644
index 00000000000..dade44d145b
--- /dev/null
+++ b/tests/components/dew_point/test.esp8266-ard.yaml
@@ -0,0 +1 @@
+<<: !include common.yaml
diff --git a/tests/components/dew_point/test.rp2040-ard.yaml b/tests/components/dew_point/test.rp2040-ard.yaml
new file mode 100644
index 00000000000..dade44d145b
--- /dev/null
+++ b/tests/components/dew_point/test.rp2040-ard.yaml
@@ -0,0 +1 @@
+<<: !include common.yaml
diff --git a/tests/unit_tests/test_main.py b/tests/unit_tests/test_main.py
index 4c7f86e2441..b8534611517 100644
--- a/tests/unit_tests/test_main.py
+++ b/tests/unit_tests/test_main.py
@@ -3722,38 +3722,38 @@ esp32:
     assert "secrets.yaml" not in summary_section
 
 
-def test_get_configured_xtal_freq_reads_sdkconfig(setup_core: Path) -> None:
+def test_get_configured_xtal_freq_reads_sdkconfig(tmp_path: Path) -> None:
     """Test reading XTAL_FREQ from sdkconfig."""
     CORE.name = "test-device"
-    CORE.build_path = setup_core
-    sdkconfig = setup_core / "sdkconfig.test-device"
+    CORE.build_path = tmp_path
+    sdkconfig = tmp_path / "sdkconfig.test-device"
     sdkconfig.write_text(
         "CONFIG_SOC_XTAL_SUPPORT_26M=y\nCONFIG_XTAL_FREQ=26\nCONFIG_XTAL_FREQ_26=y\n"
     )
     assert _get_configured_xtal_freq() == 26
 
 
-def test_get_configured_xtal_freq_default_40(setup_core: Path) -> None:
+def test_get_configured_xtal_freq_default_40(tmp_path: Path) -> None:
     """Test reading default 40MHz XTAL_FREQ from sdkconfig."""
     CORE.name = "test-device"
-    CORE.build_path = setup_core
-    sdkconfig = setup_core / "sdkconfig.test-device"
+    CORE.build_path = tmp_path
+    sdkconfig = tmp_path / "sdkconfig.test-device"
     sdkconfig.write_text("CONFIG_XTAL_FREQ=40\nCONFIG_XTAL_FREQ_40=y\n")
     assert _get_configured_xtal_freq() == 40
 
 
-def test_get_configured_xtal_freq_missing_file(setup_core: Path) -> None:
+def test_get_configured_xtal_freq_missing_file(tmp_path: Path) -> None:
     """Test that missing sdkconfig returns None."""
     CORE.name = "test-device"
-    CORE.build_path = setup_core
+    CORE.build_path = tmp_path
     assert _get_configured_xtal_freq() is None
 
 
-def test_get_configured_xtal_freq_no_xtal_line(setup_core: Path) -> None:
+def test_get_configured_xtal_freq_no_xtal_line(tmp_path: Path) -> None:
     """Test that sdkconfig without XTAL_FREQ returns None."""
     CORE.name = "test-device"
-    CORE.build_path = setup_core
-    sdkconfig = setup_core / "sdkconfig.test-device"
+    CORE.build_path = tmp_path
+    sdkconfig = tmp_path / "sdkconfig.test-device"
     sdkconfig.write_text("CONFIG_OTHER=123\n")
     assert _get_configured_xtal_freq() is None
 
diff --git a/tests/unit_tests/test_util.py b/tests/unit_tests/test_util.py
index ca3fd9b78ab..ff58fb13944 100644
--- a/tests/unit_tests/test_util.py
+++ b/tests/unit_tests/test_util.py
@@ -2,9 +2,12 @@
 
 from __future__ import annotations
 
+from collections.abc import Callable
+import io
 from pathlib import Path
 import subprocess
 import sys
+from typing import Any
 from unittest.mock import MagicMock, patch
 
 import pytest
@@ -407,6 +410,178 @@ def test_shlex_quote_edge_cases() -> None:
     assert util.shlex_quote("   ") == "'   '"
 
 
+def _make_redirect(
+    line_callbacks: list[Callable[[str], str | None]] | None = None,
+    filter_lines: list[str] | None = None,
+) -> tuple[util.RedirectText, io.StringIO]:
+    """Create a RedirectText that writes to a StringIO buffer."""
+    buf = io.StringIO()
+    redirect = util.RedirectText(
+        buf, filter_lines=filter_lines, line_callbacks=line_callbacks
+    )
+    return redirect, buf
+
+
+def test_redirect_text_callback_called_on_matching_line() -> None:
+    """Test that a line callback is called and its output is written."""
+    results: list[str] = []
+
+    def callback(line: str) -> str | None:
+        results.append(line)
+        if "target" in line:
+            return "CALLBACK OUTPUT\n"
+        return None
+
+    redirect, buf = _make_redirect(line_callbacks=[callback])
+    redirect.write("some target line\n")
+
+    assert "some target line" in buf.getvalue()
+    assert "CALLBACK OUTPUT" in buf.getvalue()
+    assert len(results) == 1
+
+
+def test_redirect_text_callback_not_triggered_on_non_matching_line() -> None:
+    """Test that callback returns None for non-matching lines."""
+
+    def callback(line: str) -> str | None:
+        if "target" in line:
+            return "FOUND\n"
+        return None
+
+    redirect, buf = _make_redirect(line_callbacks=[callback])
+    redirect.write("no match here\n")
+
+    assert "no match here" in buf.getvalue()
+    assert "FOUND" not in buf.getvalue()
+
+
+def test_redirect_text_callback_works_without_filter_pattern() -> None:
+    """Test that callbacks fire even when no filter_lines is set."""
+
+    def callback(line: str) -> str | None:
+        if "Crystal" in line:
+            return "WARNING: mismatch\n"
+        return None
+
+    redirect, buf = _make_redirect(line_callbacks=[callback])
+    redirect.write("Crystal frequency:  26MHz\n")
+
+    assert "Crystal frequency:  26MHz" in buf.getvalue()
+    assert "WARNING: mismatch" in buf.getvalue()
+
+
+def test_redirect_text_callback_works_with_filter_pattern() -> None:
+    """Test that callbacks fire alongside filter patterns."""
+
+    def callback(line: str) -> str | None:
+        if "important" in line:
+            return "NOTED\n"
+        return None
+
+    redirect, buf = _make_redirect(
+        line_callbacks=[callback],
+        filter_lines=[r"^skip this.*"],
+    )
+    redirect.write("skip this line\n")
+    redirect.write("important line\n")
+
+    assert "skip this" not in buf.getvalue()
+    assert "important line" in buf.getvalue()
+    assert "NOTED" in buf.getvalue()
+
+
+def test_redirect_text_multiple_callbacks() -> None:
+    """Test that multiple callbacks are all invoked."""
+
+    def callback_a(line: str) -> str | None:
+        if "test" in line:
+            return "FROM A\n"
+        return None
+
+    def callback_b(line: str) -> str | None:
+        if "test" in line:
+            return "FROM B\n"
+        return None
+
+    redirect, buf = _make_redirect(line_callbacks=[callback_a, callback_b])
+    redirect.write("test line\n")
+
+    output = buf.getvalue()
+    assert "FROM A" in output
+    assert "FROM B" in output
+
+
+def test_redirect_text_incomplete_line_buffered() -> None:
+    """Test that incomplete lines are buffered until newline."""
+    results: list[str] = []
+
+    def callback(line: str) -> str | None:
+        results.append(line)
+        return None
+
+    redirect, buf = _make_redirect(line_callbacks=[callback])
+    redirect.write("partial")
+    assert len(results) == 0
+
+    redirect.write(" line\n")
+    assert len(results) == 1
+    assert results[0] == "partial line"
+
+
+def test_run_external_command_line_callbacks(capsys: pytest.CaptureFixture) -> None:
+    """Test that run_external_command passes line_callbacks to RedirectText."""
+    results: list[str] = []
+
+    def callback(line: str) -> str | None:
+        results.append(line)
+        if "hello" in line:
+            return "CALLBACK FIRED\n"
+        return None
+
+    def fake_main() -> int:
+        print("hello world")
+        return 0
+
+    rc = util.run_external_command(fake_main, "fake", line_callbacks=[callback])
+
+    assert rc == 0
+    assert len(results) == 1
+    assert "hello world" in results[0]
+    captured = capsys.readouterr()
+    assert "CALLBACK FIRED" in captured.out
+
+
+def test_run_external_process_line_callbacks() -> None:
+    """Test that run_external_process passes line_callbacks to RedirectText."""
+    results: list[str] = []
+
+    def callback(line: str) -> str | None:
+        results.append(line)
+        if "from subprocess" in line:
+            return "PROCESS CALLBACK\n"
+        return None
+
+    with patch("esphome.util.subprocess.run") as mock_run:
+
+        def run_side_effect(*args: Any, **kwargs: Any) -> MagicMock:
+            # Simulate subprocess writing to the stdout RedirectText
+            stdout = kwargs.get("stdout")
+            if stdout is not None and isinstance(stdout, util.RedirectText):
+                stdout.write("from subprocess\n")
+            return MagicMock(returncode=0)
+
+        mock_run.side_effect = run_side_effect
+
+        rc = util.run_external_process(
+            "echo",
+            "test",
+            line_callbacks=[callback],
+        )
+
+    assert rc == 0
+    assert any("from subprocess" in r for r in results)
+
+
 def test_get_picotool_path_found(tmp_path: Path) -> None:
     """Test picotool path derivation from cc_path."""
     # Create the expected directory structure