diff --git a/esphome/components/esp32_ble/__init__.py b/esphome/components/esp32_ble/__init__.py
index 79d05049bf..c7b6b40394 100644
--- a/esphome/components/esp32_ble/__init__.py
+++ b/esphome/components/esp32_ble/__init__.py
@@ -7,6 +7,7 @@ from typing import Any
 
 from esphome import automation
 import esphome.codegen as cg
+from esphome.components.const import CONF_USE_PSRAM
 from esphome.components.esp32 import add_idf_sdkconfig_option, const, get_esp32_variant
 from esphome.components.esp32.const import VARIANT_ESP32C2
 import esphome.config_validation as cv
@@ -342,6 +343,9 @@ CONFIG_SCHEMA = cv.Schema(
         cv.Optional(CONF_MAX_CONNECTIONS, default=DEFAULT_MAX_CONNECTIONS): cv.All(
             cv.positive_int, cv.Range(min=1, max=IDF_MAX_CONNECTIONS)
         ),
+        cv.Optional(CONF_USE_PSRAM): cv.All(
+            cv.only_on_esp32, cv.requires_component("psram"), cv.boolean
+        ),
     }
 ).extend(cv.COMPONENT_SCHEMA)
 
@@ -598,6 +602,22 @@ async def to_code(config):
     add_idf_sdkconfig_option("CONFIG_BT_ENABLED", True)
     add_idf_sdkconfig_option("CONFIG_BT_BLE_42_FEATURES_SUPPORTED", True)
 
+    # When PSRAM and BT are used together, Bluedroid should prefer SPIRAM for
+    # heap allocations and use dynamic (heap-based) environment memory tables
+    # instead of large static DRAM arrays. This frees ~40 kB of internal RAM.
+    # Reference: Espressif ADF Design Considerations
+    # https://espressif-docs.readthedocs-hosted.com/projects/esp-adf/en/latest/
+    #            design-guide/design-considerations.html
+    if config.get(CONF_USE_PSRAM, False):
+        cg.add_define("USE_ESP32_BLE_PSRAM")
+        # CONFIG_BT_ALLOCATION_FROM_SPIRAM_FIRST is only available on ESP32
+        # (BTDM dual-mode controller). BLE-only SoCs (C3, S3, C2, H2) do not
+        # expose this Kconfig symbol; applying it there would cause a build error.
+        if get_esp32_variant() == const.VARIANT_ESP32:
+            add_idf_sdkconfig_option("CONFIG_BT_ALLOCATION_FROM_SPIRAM_FIRST", True)
+        # CONFIG_BT_BLE_DYNAMIC_ENV_MEMORY applies to all Bluedroid-enabled variants.
+        add_idf_sdkconfig_option("CONFIG_BT_BLE_DYNAMIC_ENV_MEMORY", True)
+
     # Register the core BLE loggers that are always needed
     register_bt_logger(BTLoggers.GAP, BTLoggers.BTM, BTLoggers.HCI)
 
diff --git a/esphome/components/esp32_ble/ble.cpp b/esphome/components/esp32_ble/ble.cpp
index 0280439731..ebb44c7d91 100644
--- a/esphome/components/esp32_ble/ble.cpp
+++ b/esphome/components/esp32_ble/ble.cpp
@@ -667,6 +667,9 @@ void ESP32BLE::dump_config() {
                   "  MAC address: %s\n"
                   "  IO Capability: %s",
                   mac_s, io_capability_s);
+#ifdef USE_ESP32_BLE_PSRAM
+    ESP_LOGCONFIG(TAG, "  PSRAM BLE allocation: enabled");
+#endif
 
 #ifdef ESPHOME_ESP32_BLE_EXTENDED_AUTH_PARAMS
     const char *auth_req_mode_s = "<default>";
diff --git a/esphome/components/sensor/__init__.py b/esphome/components/sensor/__init__.py
index 8dcb7165e3..43fbc98953 100644
--- a/esphome/components/sensor/__init__.py
+++ b/esphome/components/sensor/__init__.py
@@ -118,6 +118,7 @@ from esphome.schema_extractors import SCHEMA_EXTRACT, schema_extractor
 from esphome.util import Registry
 
 CODEOWNERS = ["@esphome/core"]
+
 DEVICE_CLASSES = [
     DEVICE_CLASS_ABSOLUTE_HUMIDITY,
     DEVICE_CLASS_APPARENT_POWER,
@@ -293,6 +294,7 @@ SensorInRangeCondition = sensor_ns.class_("SensorInRangeCondition", Filter)
 ClampFilter = sensor_ns.class_("ClampFilter", Filter)
 RoundFilter = sensor_ns.class_("RoundFilter", Filter)
 RoundMultipleFilter = sensor_ns.class_("RoundMultipleFilter", Filter)
+RoundSignificantDigitsFilter = sensor_ns.class_("RoundSignificantDigitsFilter", Filter)
 
 validate_unit_of_measurement = cv.All(
     cv.string_strict,
@@ -900,6 +902,18 @@ async def round_multiple_filter_to_code(config, filter_id):
     )
 
 
+@FILTER_REGISTRY.register(
+    "round_to_significant_digits",
+    RoundSignificantDigitsFilter,
+    cv.int_range(min=1, max=6),
+)
+async def round_significant_digits_filter_to_code(config, filter_id):
+    return cg.new_Pvariable(
+        filter_id,
+        cg.TemplateArguments(config),
+    )
+
+
 async def build_filters(config):
     return await cg.build_registry_list(FILTER_REGISTRY, config)
 
diff --git a/esphome/components/sensor/filter.h b/esphome/components/sensor/filter.h
index a91d66a8fb..917a1ce7d5 100644
--- a/esphome/components/sensor/filter.h
+++ b/esphome/components/sensor/filter.h
@@ -604,6 +604,19 @@ class RoundMultipleFilter : public Filter {
   float multiple_;
 };
 
+template<uint8_t Digits> class RoundSignificantDigitsFilter : public Filter {
+ public:
+  optional<float> new_value(float value) override {
+    if (std::isfinite(value)) {
+      if (value == 0.0f)
+        return 0.0f;
+      float factor = pow10_int(Digits - 1 - ilog10(value));
+      return roundf(value * factor) / factor;
+    }
+    return value;
+  }
+};
+
 class ToNTCResistanceFilter : public Filter {
  public:
   ToNTCResistanceFilter(double a, double b, double c) : a_(a), b_(b), c_(c) {}
diff --git a/esphome/core/defines.h b/esphome/core/defines.h
index 0fb7221571..07cac97e17 100644
--- a/esphome/core/defines.h
+++ b/esphome/core/defines.h
@@ -48,6 +48,7 @@
 #define USE_ENTITY_DEVICE_CLASS
 #define USE_ENTITY_ICON
 #define USE_ENTITY_UNIT_OF_MEASUREMENT
+#define USE_ESP32_BLE_PSRAM
 #define USE_ESP32_CAMERA_JPEG_CONVERSION
 #define USE_ESP32_HOSTED
 #define USE_ESP32_IMPROV_STATE_CALLBACK
diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index 86feaaca17..e71da95e6b 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -413,6 +413,23 @@ ParseOnOffState parse_on_off(const char *str, const char *on, const char *off) {
   return PARSE_NONE;
 }
 
+int8_t ilog10(float value) {
+  float abs_val = fabsf(value);
+  int8_t exp = 0;
+  if (abs_val >= 10.0f) {
+    while (abs_val >= 10.0f) {
+      abs_val /= 10.0f;
+      exp++;
+    }
+  } else if (abs_val < 1.0f) {
+    while (abs_val < 1.0f) {
+      abs_val *= 10.0f;
+      exp--;
+    }
+  }
+  return exp;
+}
+
 static inline void normalize_accuracy_decimals(float &value, int8_t &accuracy_decimals) {
   if (accuracy_decimals < 0) {
     float divisor;
diff --git a/esphome/core/helpers.h b/esphome/core/helpers.h
index bceef85490..4a91c46074 100644
--- a/esphome/core/helpers.h
+++ b/esphome/core/helpers.h
@@ -740,6 +740,11 @@ template<size_t STACK_SIZE, typename T = uint8_t> class SmallBufferWithHeapFallb
 /// @name Mathematics
 ///@{
 
+/// Compute floor(log10(fabs(value))) using iterative comparison.
+/// Avoids pulling in __ieee754_logf/log10f (~1KB flash).
+/// Only valid for finite, non-zero values.
+int8_t ilog10(float value);
+
 /// Compute 10^exp using iterative multiplication/division.
 /// Avoids pulling in powf/__ieee754_powf (~2.3KB flash) for small integer exponents.  // NOLINT
 /// Matches powf(10, exp) for the int8_t exponent range used by sensor accuracy_decimals.  // NOLINT
diff --git a/tests/components/core/helpers_test.cpp b/tests/components/core/helpers_test.cpp
new file mode 100644
index 0000000000..468185787f
--- /dev/null
+++ b/tests/components/core/helpers_test.cpp
@@ -0,0 +1,58 @@
+#include <gtest/gtest.h>
+#include <cmath>
+#include "esphome/core/helpers.h"
+
+namespace esphome {
+
+TEST(HelpersTest, Ilog10PowersOfTen) {
+  EXPECT_EQ(ilog10(1.0f), 0);
+  EXPECT_EQ(ilog10(10.0f), 1);
+  EXPECT_EQ(ilog10(100.0f), 2);
+  EXPECT_EQ(ilog10(1000.0f), 3);
+  EXPECT_EQ(ilog10(10000.0f), 4);
+  EXPECT_EQ(ilog10(100000.0f), 5);
+  EXPECT_EQ(ilog10(0.1f), -1);
+  EXPECT_EQ(ilog10(0.001f), -3);
+}
+
+TEST(HelpersTest, Ilog10General) {
+  EXPECT_EQ(ilog10(5.0f), 0);
+  EXPECT_EQ(ilog10(9.99f), 0);
+  EXPECT_EQ(ilog10(50.0f), 1);
+  EXPECT_EQ(ilog10(99.0f), 1);
+  EXPECT_EQ(ilog10(999.0f), 2);
+  EXPECT_EQ(ilog10(0.5f), -1);
+  EXPECT_EQ(ilog10(0.0072f), -3);
+  EXPECT_EQ(ilog10(120000.0f), 5);
+  EXPECT_EQ(ilog10(123456.789f), 5);
+}
+
+TEST(HelpersTest, Ilog10Negative) {
+  EXPECT_EQ(ilog10(-1.0f), 0);
+  EXPECT_EQ(ilog10(-10.0f), 1);
+  EXPECT_EQ(ilog10(-0.1f), -1);
+  EXPECT_EQ(ilog10(-123.456f), 2);
+}
+
+// Verify that ilog10 + pow10_int produces the same rounding result as log10/pow.
+// ilog10 may differ from floor(log10f()) for values not exactly representable in float
+// (e.g. 0.01f is 0.00999...), but the full round-trip must match.
+TEST(HelpersTest, Ilog10RoundTripMatchesLog10) {
+  float values[] = {0.0072f, 0.05f,   0.1f,     0.5f,     1.0f,      3.14f,     9.99f, 10.0f, 42.0f,     100.0f,
+                    1234.5f, 9999.0f, 10000.0f, 99999.0f, 120000.0f, 999999.0f, -1.0f, -0.1f, -123.456f, -10000.0f};
+  for (uint8_t digits = 1; digits <= 6; digits++) {
+    for (float v : values) {
+      // New implementation using ilog10 + pow10_int
+      float factor_new = pow10_int(digits - 1 - ilog10(v));
+      float result_new = roundf(v * factor_new) / factor_new;
+
+      // Reference using log10/pow
+      double factor_ref = pow(10.0, digits - std::ceil(std::log10(std::fabs(v))));
+      float result_ref = static_cast<float>(round(v * factor_ref) / factor_ref);
+
+      EXPECT_FLOAT_EQ(result_new, result_ref) << "mismatch for value=" << v << " digits=" << (int) digits;
+    }
+  }
+}
+
+}  // namespace esphome
diff --git a/tests/components/esp32_ble/common_use_psram.yaml b/tests/components/esp32_ble/common_use_psram.yaml
new file mode 100644
index 0000000000..cce6cf547f
--- /dev/null
+++ b/tests/components/esp32_ble/common_use_psram.yaml
@@ -0,0 +1,4 @@
+esp32_ble:
+  use_psram: true
+
+psram:
diff --git a/tests/components/esp32_ble/test.esp32-ard.yaml b/tests/components/esp32_ble/test.esp32-ard.yaml
index dade44d145..fa7b9befc7 100644
--- a/tests/components/esp32_ble/test.esp32-ard.yaml
+++ b/tests/components/esp32_ble/test.esp32-ard.yaml
@@ -1 +1,2 @@
 <<: !include common.yaml
+<<: !include common_use_psram.yaml
diff --git a/tests/components/esp32_ble/test.esp32-idf.yaml b/tests/components/esp32_ble/test.esp32-idf.yaml
index f8defaf28f..0b2a920c60 100644
--- a/tests/components/esp32_ble/test.esp32-idf.yaml
+++ b/tests/components/esp32_ble/test.esp32-idf.yaml
@@ -1,4 +1,5 @@
 <<: !include common.yaml
+<<: !include common_use_psram.yaml
 
 esp32_ble:
   io_capability: keyboard_only
diff --git a/tests/components/esp32_ble/test.esp32-p4-idf.yaml b/tests/components/esp32_ble/test.esp32-p4-idf.yaml
index 4eeb7c2f18..170220bf48 100644
--- a/tests/components/esp32_ble/test.esp32-p4-idf.yaml
+++ b/tests/components/esp32_ble/test.esp32-p4-idf.yaml
@@ -2,6 +2,7 @@ packages:
   ble: !include ../../test_build_components/common/ble/esp32-p4-idf.yaml
 
 <<: !include common.yaml
+<<: !include common_use_psram.yaml
 
 esp32_ble:
   io_capability: keyboard_only
diff --git a/tests/components/template/common-base.yaml b/tests/components/template/common-base.yaml
index ed398b0abd..ecc65de66c 100644
--- a/tests/components/template/common-base.yaml
+++ b/tests/components/template/common-base.yaml
@@ -171,6 +171,7 @@ sensor:
               quantile: .9
           - round: 1
       - round_to_multiple_of: 0.25
+      - round_to_significant_digits: 3
       - skip_initial: 3
       - sliding_window_moving_average:
           window_size: 15