diff --git a/libc/test/src/math/exhaustive/logf_test.cpp b/libc/test/src/math/exhaustive/logf_test.cpp
@@ -0,0 +1,26 @@
+//===-- Exhaustive test for logf ------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/math/logf.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+#include "utils/UnitTest/FPMatcher.h"
+#include "utils/UnitTest/Test.h"
+
+using FPBits = __llvm_libc::fputil::FPBits<float>;
+
+namespace mpfr = __llvm_libc::testing::mpfr;
+
+TEST(LlvmLibcLogfExhaustiveTest, AllValues) {
+  uint32_t bits = 0U;
+  do {
+    FPBits xbits(bits);
+    float x = float(xbits);
+    EXPECT_MPFR_MATCH(mpfr::Operation::Log, x, __llvm_libc::logf(x), 0.5);
+  } while (bits++ < 0x7f7f'ffffU);
+}
diff --git a/libc/test/src/math/logf_test.cpp b/libc/test/src/math/logf_test.cpp
@@ -0,0 +1,64 @@
+//===-- Unittests for logf-----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/math/logf.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+#include "utils/UnitTest/FPMatcher.h"
+#include "utils/UnitTest/Test.h"
+#include <math.h>
+
+#include <errno.h>
+#include <stdint.h>
+
+namespace mpfr = __llvm_libc::testing::mpfr;
+
+DECLARE_SPECIAL_CONSTANTS(float)
+
+TEST(LlvmLibcLogfTest, SpecialNumbers) {
+  EXPECT_FP_EQ(aNaN, __llvm_libc::logf(aNaN));
+  EXPECT_FP_EQ(inf, __llvm_libc::logf(inf));
+  EXPECT_TRUE(isnan(__llvm_libc::logf(neg_inf)));
+  EXPECT_FP_EQ(neg_inf, __llvm_libc::logf(0.0f));
+  EXPECT_FP_EQ(neg_inf, __llvm_libc::logf(-0.0f));
+  EXPECT_TRUE(isnan(__llvm_libc::logf(-1.0f)));
+  EXPECT_FP_EQ(zero, __llvm_libc::logf(1.0f));
+}
+
+TEST(LlvmLibcLogfTest, TrickyInputs) {
+  constexpr int N = 24;
+  constexpr uint32_t INPUTS[N] = {
+      0x3509dcf6U, 0x3bf86ef0U, 0x3ca1c99fU, 0x3d13e105U, 0x3f7ff1f2U,
+      0x3f7fffffU, 0x3f800006U, 0x3f800014U, 0x3f80001cU, 0x3f80c777U,
+      0x3f80ce72U, 0x3f80d19fU, 0x3f80f7bfU, 0x3f80fcfeU, 0x3f81feb4U,
+      0x3f83d731U, 0x3f90cb1dU, 0x3fc55379U, 0x3fd364d7U, 0x41178febU,
+      0x4c5d65a5U, 0x4e85f412U, 0x65d890d3U, 0x6f31a8ecU};
+  for (int i = 0; i < N; ++i) {
+    float x = float(FPBits(INPUTS[i]));
+    EXPECT_MPFR_MATCH(mpfr::Operation::Log, x, __llvm_libc::logf(x), 0.5);
+  }
+}
+
+TEST(LlvmLibcLogfTest, InFloatRange) {
+  constexpr uint32_t count = 1000000;
+  constexpr uint32_t step = UINT32_MAX / count;
+  for (uint32_t i = 0, v = 0; i <= count; ++i, v += step) {
+    float x = float(FPBits(v));
+    if (isnan(x) || isinf(x))
+      continue;
+    errno = 0;
+    float result = __llvm_libc::logf(x);
+    // If the computation resulted in an error or did not produce valid result
+    // in the single-precision floating point range, then ignore comparing with
+    // MPFR result as MPFR can still produce valid results because of its
+    // wider precision.
+    if (isnan(result) || isinf(result) || errno != 0)
+      continue;
+    ASSERT_MPFR_MATCH(mpfr::Operation::Log, x, __llvm_libc::logf(x), 0.5);
+  }
+}
diff --git a/libc/utils/MPFRWrapper/MPFRUtils.cpp b/libc/utils/MPFRWrapper/MPFRUtils.cpp
@@ -165,6 +165,12 @@ class MPFRNumber {
     return result;
   }
 
+  MPFRNumber log() const {
+    MPFRNumber result;
+    mpfr_log(result.value, value, MPFR_RNDN);
+    return result;
+  }
+
   MPFRNumber remquo(const MPFRNumber &divisor, int &quotient) {
     MPFRNumber remainder;
     long q;
@@ -385,6 +391,8 @@ unaryOperation(Operation op, InputType input) {
     return mpfrInput.expm1();
   case Operation::Floor:
     return mpfrInput.floor();
+  case Operation::Log:
+    return mpfrInput.log();
   case Operation::Mod2PI:
     return mpfrInput.mod_2pi();
   case Operation::ModPIOver2:

diff --git a/libc/utils/MPFRWrapper/MPFRUtils.h b/libc/utils/MPFRWrapper/MPFRUtils.h
@@ -30,6 +30,7 @@ enum class Operation : int {
   Exp2,
   Expm1,
   Floor,
+  Log,
   Mod2PI,
   ModPIOver2,
   ModPIOver4,
-Original file line number
+Diff line change
@@ Expand Up / @@ -30,6 +30,7 @@ enum class Operation : int { @@
       Exp2,
       Expm1,
       Floor,
+      Log,
       Mod2PI,
       ModPIOver2,
       ModPIOver4,
@@ Expand Down @@