diff --git a/common_audio/smoothing_filter.cc b/common_audio/smoothing_filter.cc
index e5ce987786..422eaebd14 100644
--- a/common_audio/smoothing_filter.cc
+++ b/common_audio/smoothing_filter.cc
@@ -10,6 +10,7 @@
 
 #include "common_audio/smoothing_filter.h"
 
+#include <math.h>
 #include <cmath>
 
 #include "rtc_base/checks.h"
@@ -71,7 +72,7 @@ bool SmoothingFilterImpl::SetTimeConstantMs(int time_constant_ms) {
 }
 
 void SmoothingFilterImpl::UpdateAlpha(int time_constant_ms) {
-  alpha_ = time_constant_ms == 0 ? 0.0f : exp(-1.0f / time_constant_ms);
+  alpha_ = time_constant_ms == 0 ? 0.0f : std::exp(-1.0f / time_constant_ms);
 }
 
 void SmoothingFilterImpl::ExtrapolateLastSample(int64_t time_ms) {
@@ -93,12 +94,12 @@ void SmoothingFilterImpl::ExtrapolateLastSample(int64_t time_ms) {
       multiplier = 0.0f;
     } else if (init_time_ms_ == 1) {
       // This means |init_factor_| = 1.
-      multiplier = exp(last_state_time_ms_ - time_ms);
+      multiplier = std::exp(last_state_time_ms_ - time_ms);
     } else {
-      multiplier =
-          exp(-(powf(init_factor_, last_state_time_ms_ - *init_end_time_ms_) -
-                powf(init_factor_, time_ms - *init_end_time_ms_)) /
-              init_const_);
+      multiplier = std::exp(
+          -(powf(init_factor_, last_state_time_ms_ - *init_end_time_ms_) -
+            powf(init_factor_, time_ms - *init_end_time_ms_)) /
+          init_const_);
     }
   } else {
     if (last_state_time_ms_ < *init_end_time_ms_) {
diff --git a/common_audio/smoothing_filter_unittest.cc b/common_audio/smoothing_filter_unittest.cc
index 5f6711e53d..caf9943700 100644
--- a/common_audio/smoothing_filter_unittest.cc
+++ b/common_audio/smoothing_filter_unittest.cc
@@ -122,7 +122,8 @@ TEST(SmoothingFilterTest, InitTimeEqualsOne) {
   constexpr int kInitTimeMs = 1;
   SmoothingFilterStates states(kInitTimeMs);
   CheckOutput(&states, 1.0f, 1, 1.0f);
-  CheckOutput(&states, 0.5f, 1, 1.0f * exp(-1.0f) + (1.0f - exp(-1.0f)) * 0.5f);
+  CheckOutput(&states, 0.5f, 1,
+              1.0f * std::exp(-1.0f) + (1.0f - std::exp(-1.0f)) * 0.5f);
 }
 
 TEST(SmoothingFilterTest, GetAverageOutputsEmptyBeforeFirstSample) {
@@ -144,17 +145,19 @@ TEST(SmoothingFilterTest, CannotChangeTimeConstantDuringInitialization) {
   states.smoothing_filter.AddSample(0.0);
 
   EXPECT_FALSE(states.smoothing_filter.SetTimeConstantMs(kInitTimeMs * 2));
-  EXPECT_NE(exp(-1.0f / (kInitTimeMs * 2)), states.smoothing_filter.alpha());
+  EXPECT_NE(std::exp(-1.0f / (kInitTimeMs * 2)),
+            states.smoothing_filter.alpha());
 
   states.fake_clock.AdvanceTime(TimeDelta::ms(1));
   states.smoothing_filter.AddSample(0.0);
   // When initialization finishes, the time constant should be come
   // |kInitTimeConstantMs|.
-  EXPECT_FLOAT_EQ(exp(-1.0f / kInitTimeMs), states.smoothing_filter.alpha());
+  EXPECT_FLOAT_EQ(std::exp(-1.0f / kInitTimeMs),
+                  states.smoothing_filter.alpha());
 
   // After initialization, |SetTimeConstantMs| takes effect.
   EXPECT_TRUE(states.smoothing_filter.SetTimeConstantMs(kInitTimeMs * 2));
-  EXPECT_FLOAT_EQ(exp(-1.0f / (kInitTimeMs * 2)),
+  EXPECT_FLOAT_EQ(std::exp(-1.0f / (kInitTimeMs * 2)),
                   states.smoothing_filter.alpha());
 }