diff --git a/LICENSE b/LICENSE
index 5f137cfffe..27ca8e5518 100644
--- a/LICENSE
+++ b/LICENSE
@@ -486,3 +486,18 @@ appreciated but is not required.
 2. Altered source versions must be plainly marked as such, and must not be
 misrepresented as being the original software.
 3. This notice may not be removed or altered from any source distribution.
+
+
+--------------------------------------------------------------------------------
+
+javaemul/internal/Primitives contains code derived from FreeBSD's math library:
+
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+
diff --git a/jre/java/super-wasm/double_utils.js b/jre/java/super-wasm/double_utils.js
index 3e190221d2..faefc794f3 100644
--- a/jre/java/super-wasm/double_utils.js
+++ b/jre/java/super-wasm/double_utils.js
@@ -24,4 +24,17 @@ function isValidDouble(str) {
       .test(str);
 }
 
-exports = {isValidDouble};
+/**
+ * @param {number} x
+ * @param {number} y
+ * @return {number}
+ */
+function dmod(x, y) {
+  return x % y;
+}
+
+
+exports = {
+  isValidDouble,
+  dmod
+};
diff --git a/jre/java/super-wasm/j2wasm.js b/jre/java/super-wasm/j2wasm.js
index dea5233451..3880f7bebf 100644
--- a/jre/java/super-wasm/j2wasm.js
+++ b/jre/java/super-wasm/j2wasm.js
@@ -119,6 +119,7 @@ function createImportObject(userImports) {
     'j2wasm.CharUtils.charToUpperCase': CharUtils.charToUpperCase,
     'j2wasm.ConsoleUtils.log': ConsoleUtils.log,
     'j2wasm.DoubleUtils.isValidDouble': DoubleUtils.isValidDouble,
+    'j2wasm.DoubleUtils.dmod': DoubleUtils.dmod,
     'parseFloat': parseFloat,
     'performance.now': () => performance.now(),
 
diff --git a/jre/java/super-wasm/javaemul/internal/Primitives.java b/jre/java/super-wasm/javaemul/internal/Primitives.java
index 9277d869d0..cca2ced741 100644
--- a/jre/java/super-wasm/javaemul/internal/Primitives.java
+++ b/jre/java/super-wasm/javaemul/internal/Primitives.java
@@ -16,6 +16,7 @@
 package javaemul.internal;
 
 import javaemul.internal.annotations.Wasm;
+import jsinterop.annotations.JsMethod;
 
 /** Static Primitive helper. */
 public class Primitives {
@@ -195,29 +196,127 @@ public static long safeDivision(long dividend, long divisor) {
   @Wasm("i64.div_s")
   private static native long wasmDivision(long dividend, long divisor);
 
-  public static double dmod(double x, double y) {
-    if (Double.isNaN(x) || Double.isNaN(y) || Double.isInfinite(x) || y == 0.0d) {
-      return Double.NaN;
+  @JsMethod(namespace = "j2wasm.DoubleUtils")
+  public static native double dmod(double x, double y);
+
+  @SuppressWarnings("IdentityBinaryExpression")
+  public static float fmod(float x, float y) {
+    // Derived from FreeBSD's src/e_fmodf.c which came with this notice.
+    /*
+     * ====================================================
+     * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+     *
+     * Developed at SunPro, a Sun Microsystems, Inc. business.
+     * Permission to use, copy, modify, and distribute this
+     * software is freely granted, provided that this notice
+     * is preserved.
+     * ====================================================
+     */
+
+    int n, hz;
+    int hx = Platform.floatToRawIntBits(x);
+    int hy = Platform.floatToRawIntBits(y);
+    int sx = hx & 0x80000000; /* sign of x */
+    hx ^= sx; /* |x| */
+    hy &= 0x7fffffff; /* |y| */
+
+    /* purge off exception values */
+    if (hy == 0 /* y=0 */
+        || (hx >= 0x7f800000) /* or x not finite*/
+        || (hy > 0x7f800000) /* or y is NaN */) {
+      return (x * y) / (x * y);
+    }
+    if (hx < hy) {
+      return x; /* |x|<|y| return x */
+    }
+    if (hx == hy) {
+      return signedZero(sx); /* |x|=|y| return x*0 */
     }
 
-    if (Double.isInfinite(y) || x == 0.0d) {
-      return x;
+    /* determine ix = ilogb(x) */
+    int ix;
+    if (hx < 0x00800000) {
+      /* subnormal x */
+      ix = -126;
+      for (int i = (hx << 8); i > 0; i <<= 1) {
+        ix -= 1;
+      }
+    } else {
+      ix = (hx >> 23) - 127;
     }
-    // See https://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.17.3
-    // and https://en.wikipedia.org/wiki/Modulo_operation#Variants_of_the_definition
-    return x - (y * narrowDoubleToInt(x / y));
-  }
 
-  public static float fmod(float x, float y) {
-    if (Float.isNaN(x) || Float.isNaN(y) || Float.isInfinite(x) || y == 0.0f) {
-      return Float.NaN;
+    /* determine iy = ilogb(y) */
+    int iy;
+    if (hy < 0x00800000) {
+      /* subnormal y */
+      iy = -126;
+      for (int i = (hy << 8); i >= 0; i <<= 1) {
+        iy -= 1;
+      }
+    } else {
+      iy = (hy >> 23) - 127;
+    }
+
+    /* set up {hx,lx}, {hy,ly} and align y to x */
+    if (ix >= -126) {
+      hx = 0x00800000 | (0x007fffff & hx);
+    } else {
+      /* subnormal x, shift x to normal */
+      n = -126 - ix;
+      hx = hx << n;
+    }
+    if (iy >= -126) {
+      hy = 0x00800000 | (0x007fffff & hy);
+    } else {
+      /* subnormal y, shift y to normal */
+      n = -126 - iy;
+      hy = hy << n;
+    }
+
+    /* fix point fmod */
+    n = ix - iy;
+    while (n-- != 0) {
+      hz = hx - hy;
+      if (hz < 0) {
+        hx = hx + hx;
+      } else {
+        if (hz == 0) {
+          return signedZero(sx);
+        }
+        hx = hz + hz;
+      }
+    }
+    hz = hx - hy;
+    if (hz >= 0) {
+      hx = hz;
     }
 
-    if (Float.isInfinite(y) || x == 0.0f) {
-      return x;
+    /* convert back to floating value and restore the sign */
+    if (hx == 0) {
+      return signedZero(sx);
     }
+    while (hx < 0x00800000) {
+      /* normalize x */
+      hx = hx + hx;
+      iy -= 1;
+    }
+    if (iy >= -126) {
+      /* normalize output */
+      hx = ((hx - 0x00800000) | ((iy + 127) << 23));
+      x = Float.intBitsToFloat(hx | sx);
+    } else {
+      /* subnormal output */
+      n = -126 - iy;
+      hx >>= n;
+      x = Float.intBitsToFloat(hx | sx);
+      x *= 1.0f; /* create necessary signal */
+    }
+
+    return x; /* exact output */
+  }
 
-    return x - (y * narrowFloatToInt(x / y));
+  private static float signedZero(int sx) {
+    return sx == 0 ? .0f : -.0f;
   }
 
   /** Narrows a number to an unsigned 16-bit number. */
diff --git a/transpiler/javatests/com/google/j2cl/integration/java/binaryexpressions/Main.java b/transpiler/javatests/com/google/j2cl/integration/java/binaryexpressions/Main.java
index 5ff0b5865c..39821d0871 100644
--- a/transpiler/javatests/com/google/j2cl/integration/java/binaryexpressions/Main.java
+++ b/transpiler/javatests/com/google/j2cl/integration/java/binaryexpressions/Main.java
@@ -15,6 +15,7 @@
  */
 package binaryexpressions;
 
+import static com.google.j2cl.integration.testing.Asserts.assertEquals;
 import static com.google.j2cl.integration.testing.Asserts.assertEqualsDelta;
 import static com.google.j2cl.integration.testing.Asserts.assertTrue;
 
@@ -110,8 +111,16 @@ private static void testFloatingPointRemainder() {
     assertTrue(Double.isNaN(-1.2 % 0.0));
     assertTrue(1.2 % Double.POSITIVE_INFINITY == 1.2);
     assertTrue(1.2 % Double.NEGATIVE_INFINITY == 1.2);
-    assertTrue(0.0 % 1.2 == 0.0);
-    assertTrue(-0.0 % 1.2 == -0.0);
+    assertTrue(Long.MAX_VALUE % 3.0 == 2.0);
+    assertTrue(Long.MAX_VALUE % -3.0 == 2.0);
+    assertTrue(Long.MIN_VALUE % 3.0 == -2.0);
+    assertTrue(Long.MIN_VALUE % -3.0 == -2.0);
+    assertEquals(1.0 % 1.0, 0.0);
+    assertEquals(-1.0 % 1.0, -0.0);
+    assertEquals(1.0 % -1.0, 0.0);
+    assertEquals(-1.0 % -1.0, -0.0);
+    assertEquals(0.0 % 1.2, 0.0);
+    assertEquals(-0.0 % 1.2, -0.0);
     assertEqualsDelta(.2, .7 % .5, 1e-15);
     assertEqualsDelta(.2, .7 % -.5, 1e-15);
     assertEqualsDelta(-.2, -.7 % .5, 1e-15);
@@ -125,8 +134,16 @@ private static void testFloatingPointRemainder() {
     assertTrue(Float.isNaN(-1.2f % 0.0f));
     assertTrue(1.2f % Float.POSITIVE_INFINITY == 1.2f);
     assertTrue(1.2f % Float.NEGATIVE_INFINITY == 1.2f);
-    assertTrue(0.0f % 1.2f == 0.0f);
-    assertTrue(-0.0f % 1.2f == -0.0f);
+    assertTrue(Long.MAX_VALUE % 3.0f == 2.0f);
+    assertTrue(Long.MAX_VALUE % -3.0f == 2.0f);
+    assertTrue(Long.MIN_VALUE % 3.0f == -2.0f);
+    assertTrue(Long.MIN_VALUE % -3.0f == -2.0f);
+    assertEquals(1.0f % 1.0f, 0.0f);
+    assertEquals(-1.0f % 1.0f, -0.0f);
+    assertEquals(1.0f % -1.0f, 0.0f);
+    assertEquals(-1.0f % -1.0f, -0.0f);
+    assertEquals(0.0f % 1.2f, 0.0f);
+    assertEquals(-0.0f % 1.2f, -0.0f);
     assertEqualsDelta(.2f, .7f % .5f, 1e-7);
     assertEqualsDelta(.2f, .7f % -.5f, 1e-7);
     assertEqualsDelta(-.2f, -.7f % .5f, 1e-7);
diff --git a/transpiler/javatests/com/google/j2cl/readable/java/importglobaljstypes/output_wasm_imports/module.imports.js.txt b/transpiler/javatests/com/google/j2cl/readable/java/importglobaljstypes/output_wasm_imports/module.imports.js.txt
index 137ebc7c9c..6591daf8c3 100644
--- a/transpiler/javatests/com/google/j2cl/readable/java/importglobaljstypes/output_wasm_imports/module.imports.js.txt
+++ b/transpiler/javatests/com/google/j2cl/readable/java/importglobaljstypes/output_wasm_imports/module.imports.js.txt
@@ -85,6 +85,7 @@ function getImports() {
    'get RegExpResult.index': (/** !RegExpResult */ $instance, ) => $instance.index,
    'get RegExpResult.length': (/** !RegExpResult */ $instance, ) => $instance.length,
    'RegExpResult.at': (/** !RegExpResult */ $instance, /** number */ index, ) => $instance.at(index, ),
+   'j2wasm.DoubleUtils.dmod': j2wasm_DoubleUtils.dmod,
    'Number.isInteger': Number.isInteger,
    'RegExp.toString': (/** !RegExp */ $instance, ) => $instance.toString(),
   }
diff --git a/transpiler/javatests/com/google/j2cl/readable/java/nativejstypes/output_wasm_imports/module.imports.js.txt b/transpiler/javatests/com/google/j2cl/readable/java/nativejstypes/output_wasm_imports/module.imports.js.txt
index a94171c878..57b46c0159 100644
--- a/transpiler/javatests/com/google/j2cl/readable/java/nativejstypes/output_wasm_imports/module.imports.js.txt
+++ b/transpiler/javatests/com/google/j2cl/readable/java/nativejstypes/output_wasm_imports/module.imports.js.txt
@@ -88,6 +88,7 @@ function getImports() {
    'get RegExpResult.index': (/** !RegExpResult */ $instance, ) => $instance.index,
    'get RegExpResult.length': (/** !RegExpResult */ $instance, ) => $instance.length,
    'RegExpResult.at': (/** !RegExpResult */ $instance, /** number */ index, ) => $instance.at(index, ),
+   'j2wasm.DoubleUtils.dmod': j2wasm_DoubleUtils.dmod,
    'nativejstypes.Bar.constructor': (/** number */ x, /** number */ y, ) => new nativejstypes_Bar(x, y, ),
    'nativejstypes.Bar.product': (/** !nativejstypes_Bar */ $instance, ) => $instance.product(),
    'nativejstypes.Bar.getStatic': nativejstypes_Bar.getStatic,